diff --git a/extensions/default_unparsing_config.json b/extensions/default_unparsing_config.json
index 83a521465..256fd56a0 100644
--- a/extensions/default_unparsing_config.json
+++ b/extensions/default_unparsing_config.json
@@ -2049,6 +2049,33 @@
         }
       }
     },
+    "TypeAccessDef": {
+      "node": {
+        "kind": "group",
+        "document": [
+          {
+            "kind": "recurse_field",
+            "field": "f_has_not_null"
+          },
+          {
+            "kind": "text",
+            "text": "access"
+          },  
+          {
+            "kind": "recurse_field",
+            "field": "f_has_all"
+          },
+          {
+            "kind": "recurse_field",
+            "field": "f_has_constant"
+          },
+          {
+            "kind": "recurse_field",
+            "field": "f_subtype_indication"
+          }
+        ]
+      }
+    },
     "UnconstrainedArrayIndices": {
       "node": {
         "kind": "align",
diff --git a/testsuite/tests/unparsing/access_type_def/access_all/doc-baseline.json b/testsuite/tests/unparsing/access_type_def/access_all/doc-baseline.json
new file mode 100644
index 000000000..8f6c39088
--- /dev/null
+++ b/testsuite/tests/unparsing/access_type_def/access_all/doc-baseline.json
@@ -0,0 +1,138 @@
+{
+  "id": 17,
+  "kind": "command",
+  "command": {
+    "command": "group",
+    "id": 0,
+    "groupContents": {
+      "id": 16,
+      "kind": "list",
+      "list": [
+        {
+          "id": 6,
+          "kind": "command",
+          "command": {
+            "command": "group",
+            "id": 0,
+            "groupContents": {
+              "id": 5,
+              "kind": "list",
+              "list": [
+                {
+                  "id": 0,
+                  "kind": "text",
+                  "text": "type Aaaaaaaa"
+                },
+                {
+                  "id": 2,
+                  "kind": "command",
+                  "command": {
+                    "command": "align",
+                    "alignData": {
+                      "kind": "width",
+                      "n": 2
+                    },
+                    "alignContents": {
+                      "id": 1,
+                      "kind": "list",
+                      "list": [
+                      ]
+                    }
+                  }
+                },
+                {
+                  "id": 3,
+                  "kind": "command",
+                  "command": {
+                    "command": "line",
+                    "literal": false,
+                    "soft": false,
+                    "hard": false
+                  }
+                },
+                {
+                  "id": 4,
+                  "kind": "text",
+                  "text": "is"
+                }
+              ]
+            },
+            "break": false,
+            "expandedStates": null
+          }
+        },
+        {
+          "id": 14,
+          "kind": "command",
+          "command": {
+            "command": "align",
+            "alignData": {
+              "kind": "width",
+              "n": 2
+            },
+            "alignContents": {
+              "id": 13,
+              "kind": "list",
+              "list": [
+                {
+                  "id": 7,
+                  "kind": "command",
+                  "command": {
+                    "command": "line",
+                    "literal": false,
+                    "soft": false,
+                    "hard": false
+                  }
+                },
+                {
+                  "id": 12,
+                  "kind": "command",
+                  "command": {
+                    "command": "group",
+                    "id": 0,
+                    "groupContents": {
+                      "id": 11,
+                      "kind": "list",
+                      "list": [
+                        {
+                          "id": 10,
+                          "kind": "command",
+                          "command": {
+                            "command": "group",
+                            "id": 0,
+                            "groupContents": {
+                              "id": 9,
+                              "kind": "list",
+                              "list": [
+                                {
+                                  "id": 8,
+                                  "kind": "text",
+                                  "text": "access all Bbbbbbbbbbbbbbb"
+                                }
+                              ]
+                            },
+                            "break": false,
+                            "expandedStates": null
+                          }
+                        }
+                      ]
+                    },
+                    "break": false,
+                    "expandedStates": null
+                  }
+                }
+              ]
+            }
+          }
+        },
+        {
+          "id": 15,
+          "kind": "text",
+          "text": ";"
+        }
+      ]
+    },
+    "break": false,
+    "expandedStates": null
+  }
+}
diff --git a/testsuite/tests/unparsing/access_type_def/access_all/input.ada b/testsuite/tests/unparsing/access_type_def/access_all/input.ada
new file mode 100644
index 000000000..505219796
--- /dev/null
+++ b/testsuite/tests/unparsing/access_type_def/access_all/input.ada
@@ -0,0 +1 @@
+type Aaaaaaaa is access all Bbbbbbbbbbbbbbb;
diff --git a/testsuite/tests/unparsing/access_type_def/access_all/test.out b/testsuite/tests/unparsing/access_type_def/access_all/test.out
new file mode 100644
index 000000000..505219796
--- /dev/null
+++ b/testsuite/tests/unparsing/access_type_def/access_all/test.out
@@ -0,0 +1 @@
+type Aaaaaaaa is access all Bbbbbbbbbbbbbbb;
diff --git a/testsuite/tests/unparsing/access_type_def/access_all/test.yaml b/testsuite/tests/unparsing/access_type_def/access_all/test.yaml
new file mode 100644
index 000000000..8c148ee4e
--- /dev/null
+++ b/testsuite/tests/unparsing/access_type_def/access_all/test.yaml
@@ -0,0 +1,7 @@
+description: |
+    This test checks the formatting of a simple access all
+    type declaration.
+    It is expected the declaration stays on a single line.
+
+driver: unparser
+rule: type_decl
diff --git a/testsuite/tests/unparsing/access_type_def/long_subtype_indication/doc-baseline.json b/testsuite/tests/unparsing/access_type_def/long_subtype_indication/doc-baseline.json
new file mode 100644
index 000000000..ff45dd6f1
--- /dev/null
+++ b/testsuite/tests/unparsing/access_type_def/long_subtype_indication/doc-baseline.json
@@ -0,0 +1,138 @@
+{
+  "id": 17,
+  "kind": "command",
+  "command": {
+    "command": "group",
+    "id": 0,
+    "groupContents": {
+      "id": 16,
+      "kind": "list",
+      "list": [
+        {
+          "id": 6,
+          "kind": "command",
+          "command": {
+            "command": "group",
+            "id": 0,
+            "groupContents": {
+              "id": 5,
+              "kind": "list",
+              "list": [
+                {
+                  "id": 0,
+                  "kind": "text",
+                  "text": "type Aaaaaaaa"
+                },
+                {
+                  "id": 2,
+                  "kind": "command",
+                  "command": {
+                    "command": "align",
+                    "alignData": {
+                      "kind": "width",
+                      "n": 2
+                    },
+                    "alignContents": {
+                      "id": 1,
+                      "kind": "list",
+                      "list": [
+                      ]
+                    }
+                  }
+                },
+                {
+                  "id": 3,
+                  "kind": "command",
+                  "command": {
+                    "command": "line",
+                    "literal": false,
+                    "soft": false,
+                    "hard": false
+                  }
+                },
+                {
+                  "id": 4,
+                  "kind": "text",
+                  "text": "is"
+                }
+              ]
+            },
+            "break": false,
+            "expandedStates": null
+          }
+        },
+        {
+          "id": 14,
+          "kind": "command",
+          "command": {
+            "command": "align",
+            "alignData": {
+              "kind": "width",
+              "n": 2
+            },
+            "alignContents": {
+              "id": 13,
+              "kind": "list",
+              "list": [
+                {
+                  "id": 7,
+                  "kind": "command",
+                  "command": {
+                    "command": "line",
+                    "literal": false,
+                    "soft": false,
+                    "hard": false
+                  }
+                },
+                {
+                  "id": 12,
+                  "kind": "command",
+                  "command": {
+                    "command": "group",
+                    "id": 0,
+                    "groupContents": {
+                      "id": 11,
+                      "kind": "list",
+                      "list": [
+                        {
+                          "id": 10,
+                          "kind": "command",
+                          "command": {
+                            "command": "group",
+                            "id": 0,
+                            "groupContents": {
+                              "id": 9,
+                              "kind": "list",
+                              "list": [
+                                {
+                                  "id": 8,
+                                  "kind": "text",
+                                  "text": "access BBBBBBBBBBBbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb"
+                                }
+                              ]
+                            },
+                            "break": false,
+                            "expandedStates": null
+                          }
+                        }
+                      ]
+                    },
+                    "break": false,
+                    "expandedStates": null
+                  }
+                }
+              ]
+            }
+          }
+        },
+        {
+          "id": 15,
+          "kind": "text",
+          "text": ";"
+        }
+      ]
+    },
+    "break": false,
+    "expandedStates": null
+  }
+}
diff --git a/testsuite/tests/unparsing/access_type_def/long_subtype_indication/input.ada b/testsuite/tests/unparsing/access_type_def/long_subtype_indication/input.ada
new file mode 100644
index 000000000..5b4039939
--- /dev/null
+++ b/testsuite/tests/unparsing/access_type_def/long_subtype_indication/input.ada
@@ -0,0 +1 @@
+type Aaaaaaaa is access BBBBBBBBBBBbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb;
diff --git a/testsuite/tests/unparsing/access_type_def/long_subtype_indication/test.out b/testsuite/tests/unparsing/access_type_def/long_subtype_indication/test.out
new file mode 100644
index 000000000..00eceb746
--- /dev/null
+++ b/testsuite/tests/unparsing/access_type_def/long_subtype_indication/test.out
@@ -0,0 +1,2 @@
+type Aaaaaaaa is
+  access BBBBBBBBBBBbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb;
diff --git a/testsuite/tests/unparsing/access_type_def/long_subtype_indication/test.yaml b/testsuite/tests/unparsing/access_type_def/long_subtype_indication/test.yaml
new file mode 100644
index 000000000..9e7675bf5
--- /dev/null
+++ b/testsuite/tests/unparsing/access_type_def/long_subtype_indication/test.yaml
@@ -0,0 +1,8 @@
+description: |
+    This test checks the formatting of a simple access type declaration
+    having a long subtype indication.
+    It is expected the declaration be splitted after `is` keyword and
+    the new line be indented with a line continuation indentation.
+
+driver: unparser
+rule: type_decl
diff --git a/testsuite/tests/unparsing/access_type_def/long_type_name/doc-baseline.json b/testsuite/tests/unparsing/access_type_def/long_type_name/doc-baseline.json
new file mode 100644
index 000000000..55116413e
--- /dev/null
+++ b/testsuite/tests/unparsing/access_type_def/long_type_name/doc-baseline.json
@@ -0,0 +1,138 @@
+{
+  "id": 17,
+  "kind": "command",
+  "command": {
+    "command": "group",
+    "id": 0,
+    "groupContents": {
+      "id": 16,
+      "kind": "list",
+      "list": [
+        {
+          "id": 6,
+          "kind": "command",
+          "command": {
+            "command": "group",
+            "id": 0,
+            "groupContents": {
+              "id": 5,
+              "kind": "list",
+              "list": [
+                {
+                  "id": 0,
+                  "kind": "text",
+                  "text": "type Aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+                },
+                {
+                  "id": 2,
+                  "kind": "command",
+                  "command": {
+                    "command": "align",
+                    "alignData": {
+                      "kind": "width",
+                      "n": 2
+                    },
+                    "alignContents": {
+                      "id": 1,
+                      "kind": "list",
+                      "list": [
+                      ]
+                    }
+                  }
+                },
+                {
+                  "id": 3,
+                  "kind": "command",
+                  "command": {
+                    "command": "line",
+                    "literal": false,
+                    "soft": false,
+                    "hard": false
+                  }
+                },
+                {
+                  "id": 4,
+                  "kind": "text",
+                  "text": "is"
+                }
+              ]
+            },
+            "break": false,
+            "expandedStates": null
+          }
+        },
+        {
+          "id": 14,
+          "kind": "command",
+          "command": {
+            "command": "align",
+            "alignData": {
+              "kind": "width",
+              "n": 2
+            },
+            "alignContents": {
+              "id": 13,
+              "kind": "list",
+              "list": [
+                {
+                  "id": 7,
+                  "kind": "command",
+                  "command": {
+                    "command": "line",
+                    "literal": false,
+                    "soft": false,
+                    "hard": false
+                  }
+                },
+                {
+                  "id": 12,
+                  "kind": "command",
+                  "command": {
+                    "command": "group",
+                    "id": 0,
+                    "groupContents": {
+                      "id": 11,
+                      "kind": "list",
+                      "list": [
+                        {
+                          "id": 10,
+                          "kind": "command",
+                          "command": {
+                            "command": "group",
+                            "id": 0,
+                            "groupContents": {
+                              "id": 9,
+                              "kind": "list",
+                              "list": [
+                                {
+                                  "id": 8,
+                                  "kind": "text",
+                                  "text": "access Bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb"
+                                }
+                              ]
+                            },
+                            "break": false,
+                            "expandedStates": null
+                          }
+                        }
+                      ]
+                    },
+                    "break": false,
+                    "expandedStates": null
+                  }
+                }
+              ]
+            }
+          }
+        },
+        {
+          "id": 15,
+          "kind": "text",
+          "text": ";"
+        }
+      ]
+    },
+    "break": false,
+    "expandedStates": null
+  }
+}
diff --git a/testsuite/tests/unparsing/access_type_def/long_type_name/input.ada b/testsuite/tests/unparsing/access_type_def/long_type_name/input.ada
new file mode 100644
index 000000000..ad75d12b8
--- /dev/null
+++ b/testsuite/tests/unparsing/access_type_def/long_type_name/input.ada
@@ -0,0 +1 @@
+type Aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa is access Bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb;
diff --git a/testsuite/tests/unparsing/access_type_def/long_type_name/test.out b/testsuite/tests/unparsing/access_type_def/long_type_name/test.out
new file mode 100644
index 000000000..052aefcfb
--- /dev/null
+++ b/testsuite/tests/unparsing/access_type_def/long_type_name/test.out
@@ -0,0 +1,2 @@
+type Aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa is
+  access Bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb;
diff --git a/testsuite/tests/unparsing/access_type_def/long_type_name/test.yaml b/testsuite/tests/unparsing/access_type_def/long_type_name/test.yaml
new file mode 100644
index 000000000..3d695ad8d
--- /dev/null
+++ b/testsuite/tests/unparsing/access_type_def/long_type_name/test.yaml
@@ -0,0 +1,8 @@
+description: |
+    This test checks the formatting of a simple access type declaration
+    having a long type name.
+    It is expected the declaration be splitted after `is` keyword and
+    the new line be indented with a line continuation indentation.
+
+driver: unparser
+rule: type_decl
diff --git a/testsuite/tests/unparsing/access_type_def/not_null_access/doc-baseline.json b/testsuite/tests/unparsing/access_type_def/not_null_access/doc-baseline.json
new file mode 100644
index 000000000..ed2a6ad6f
--- /dev/null
+++ b/testsuite/tests/unparsing/access_type_def/not_null_access/doc-baseline.json
@@ -0,0 +1,138 @@
+{
+  "id": 17,
+  "kind": "command",
+  "command": {
+    "command": "group",
+    "id": 0,
+    "groupContents": {
+      "id": 16,
+      "kind": "list",
+      "list": [
+        {
+          "id": 6,
+          "kind": "command",
+          "command": {
+            "command": "group",
+            "id": 0,
+            "groupContents": {
+              "id": 5,
+              "kind": "list",
+              "list": [
+                {
+                  "id": 0,
+                  "kind": "text",
+                  "text": "type Aaaaaaaa"
+                },
+                {
+                  "id": 2,
+                  "kind": "command",
+                  "command": {
+                    "command": "align",
+                    "alignData": {
+                      "kind": "width",
+                      "n": 2
+                    },
+                    "alignContents": {
+                      "id": 1,
+                      "kind": "list",
+                      "list": [
+                      ]
+                    }
+                  }
+                },
+                {
+                  "id": 3,
+                  "kind": "command",
+                  "command": {
+                    "command": "line",
+                    "literal": false,
+                    "soft": false,
+                    "hard": false
+                  }
+                },
+                {
+                  "id": 4,
+                  "kind": "text",
+                  "text": "is"
+                }
+              ]
+            },
+            "break": false,
+            "expandedStates": null
+          }
+        },
+        {
+          "id": 14,
+          "kind": "command",
+          "command": {
+            "command": "align",
+            "alignData": {
+              "kind": "width",
+              "n": 2
+            },
+            "alignContents": {
+              "id": 13,
+              "kind": "list",
+              "list": [
+                {
+                  "id": 7,
+                  "kind": "command",
+                  "command": {
+                    "command": "line",
+                    "literal": false,
+                    "soft": false,
+                    "hard": false
+                  }
+                },
+                {
+                  "id": 12,
+                  "kind": "command",
+                  "command": {
+                    "command": "group",
+                    "id": 0,
+                    "groupContents": {
+                      "id": 11,
+                      "kind": "list",
+                      "list": [
+                        {
+                          "id": 10,
+                          "kind": "command",
+                          "command": {
+                            "command": "group",
+                            "id": 0,
+                            "groupContents": {
+                              "id": 9,
+                              "kind": "list",
+                              "list": [
+                                {
+                                  "id": 8,
+                                  "kind": "text",
+                                  "text": "not null access Bbbbbbbbbbbbbbb"
+                                }
+                              ]
+                            },
+                            "break": false,
+                            "expandedStates": null
+                          }
+                        }
+                      ]
+                    },
+                    "break": false,
+                    "expandedStates": null
+                  }
+                }
+              ]
+            }
+          }
+        },
+        {
+          "id": 15,
+          "kind": "text",
+          "text": ";"
+        }
+      ]
+    },
+    "break": false,
+    "expandedStates": null
+  }
+}
diff --git a/testsuite/tests/unparsing/access_type_def/not_null_access/input.ada b/testsuite/tests/unparsing/access_type_def/not_null_access/input.ada
new file mode 100644
index 000000000..400264707
--- /dev/null
+++ b/testsuite/tests/unparsing/access_type_def/not_null_access/input.ada
@@ -0,0 +1 @@
+type Aaaaaaaa is not null access Bbbbbbbbbbbbbbb;
diff --git a/testsuite/tests/unparsing/access_type_def/not_null_access/test.out b/testsuite/tests/unparsing/access_type_def/not_null_access/test.out
new file mode 100644
index 000000000..400264707
--- /dev/null
+++ b/testsuite/tests/unparsing/access_type_def/not_null_access/test.out
@@ -0,0 +1 @@
+type Aaaaaaaa is not null access Bbbbbbbbbbbbbbb;
diff --git a/testsuite/tests/unparsing/access_type_def/not_null_access/test.yaml b/testsuite/tests/unparsing/access_type_def/not_null_access/test.yaml
new file mode 100644
index 000000000..3cb9fa84b
--- /dev/null
+++ b/testsuite/tests/unparsing/access_type_def/not_null_access/test.yaml
@@ -0,0 +1,7 @@
+description: |
+    This test checks the formatting of a simple not null access
+    type declaration.
+    It is expected the declaration stays on a single line.
+
+driver: unparser
+rule: type_decl
diff --git a/testsuite/tests/unparsing/access_type_def/simple_access/doc-baseline.json b/testsuite/tests/unparsing/access_type_def/simple_access/doc-baseline.json
new file mode 100644
index 000000000..375d63e0d
--- /dev/null
+++ b/testsuite/tests/unparsing/access_type_def/simple_access/doc-baseline.json
@@ -0,0 +1,138 @@
+{
+  "id": 17,
+  "kind": "command",
+  "command": {
+    "command": "group",
+    "id": 0,
+    "groupContents": {
+      "id": 16,
+      "kind": "list",
+      "list": [
+        {
+          "id": 6,
+          "kind": "command",
+          "command": {
+            "command": "group",
+            "id": 0,
+            "groupContents": {
+              "id": 5,
+              "kind": "list",
+              "list": [
+                {
+                  "id": 0,
+                  "kind": "text",
+                  "text": "type Aaaaaaaa"
+                },
+                {
+                  "id": 2,
+                  "kind": "command",
+                  "command": {
+                    "command": "align",
+                    "alignData": {
+                      "kind": "width",
+                      "n": 2
+                    },
+                    "alignContents": {
+                      "id": 1,
+                      "kind": "list",
+                      "list": [
+                      ]
+                    }
+                  }
+                },
+                {
+                  "id": 3,
+                  "kind": "command",
+                  "command": {
+                    "command": "line",
+                    "literal": false,
+                    "soft": false,
+                    "hard": false
+                  }
+                },
+                {
+                  "id": 4,
+                  "kind": "text",
+                  "text": "is"
+                }
+              ]
+            },
+            "break": false,
+            "expandedStates": null
+          }
+        },
+        {
+          "id": 14,
+          "kind": "command",
+          "command": {
+            "command": "align",
+            "alignData": {
+              "kind": "width",
+              "n": 2
+            },
+            "alignContents": {
+              "id": 13,
+              "kind": "list",
+              "list": [
+                {
+                  "id": 7,
+                  "kind": "command",
+                  "command": {
+                    "command": "line",
+                    "literal": false,
+                    "soft": false,
+                    "hard": false
+                  }
+                },
+                {
+                  "id": 12,
+                  "kind": "command",
+                  "command": {
+                    "command": "group",
+                    "id": 0,
+                    "groupContents": {
+                      "id": 11,
+                      "kind": "list",
+                      "list": [
+                        {
+                          "id": 10,
+                          "kind": "command",
+                          "command": {
+                            "command": "group",
+                            "id": 0,
+                            "groupContents": {
+                              "id": 9,
+                              "kind": "list",
+                              "list": [
+                                {
+                                  "id": 8,
+                                  "kind": "text",
+                                  "text": "access Bbbbbbbbbbbbbbb"
+                                }
+                              ]
+                            },
+                            "break": false,
+                            "expandedStates": null
+                          }
+                        }
+                      ]
+                    },
+                    "break": false,
+                    "expandedStates": null
+                  }
+                }
+              ]
+            }
+          }
+        },
+        {
+          "id": 15,
+          "kind": "text",
+          "text": ";"
+        }
+      ]
+    },
+    "break": false,
+    "expandedStates": null
+  }
+}
diff --git a/testsuite/tests/unparsing/access_type_def/simple_access/input.ada b/testsuite/tests/unparsing/access_type_def/simple_access/input.ada
new file mode 100644
index 000000000..25742ae77
--- /dev/null
+++ b/testsuite/tests/unparsing/access_type_def/simple_access/input.ada
@@ -0,0 +1 @@
+type Aaaaaaaa is access Bbbbbbbbbbbbbbb;
diff --git a/testsuite/tests/unparsing/access_type_def/simple_access/test.out b/testsuite/tests/unparsing/access_type_def/simple_access/test.out
new file mode 100644
index 000000000..25742ae77
--- /dev/null
+++ b/testsuite/tests/unparsing/access_type_def/simple_access/test.out
@@ -0,0 +1 @@
+type Aaaaaaaa is access Bbbbbbbbbbbbbbb;
diff --git a/testsuite/tests/unparsing/access_type_def/simple_access/test.yaml b/testsuite/tests/unparsing/access_type_def/simple_access/test.yaml
new file mode 100644
index 000000000..6cfdc23bd
--- /dev/null
+++ b/testsuite/tests/unparsing/access_type_def/simple_access/test.yaml
@@ -0,0 +1,6 @@
+description: |
+    This test checks the formatting of a simple access type declaration.
+    It is expected the declaration stays on a single line.
+
+driver: unparser
+rule: type_decl