diff --git a/lib/ipaddr.ml b/lib/ipaddr.ml
index 18794c5..64e74f4 100644
--- a/lib/ipaddr.ml
+++ b/lib/ipaddr.ml
@@ -1354,6 +1354,10 @@ module Prefix = struct
     | V4 p -> V4 (V4.Prefix.netmask p)
     | V6 p -> V6 (V6.Prefix.netmask p)
 
+  let address = function
+    | V4 p -> V4 (V4.Prefix.address p)
+    | V6 p -> V6 (V6.Prefix.address p)
+
   let pp ppf i = Format.fprintf ppf "%s" (to_string i)
 
   let first = function
diff --git a/lib/ipaddr.mli b/lib/ipaddr.mli
index 62f3dec..95124ed 100644
--- a/lib/ipaddr.mli
+++ b/lib/ipaddr.mli
@@ -777,6 +777,9 @@ module Prefix : sig
   val netmask : t -> addr
   (** [netmask subnet] is the netmask for [subnet]. *)
 
+  val address : t -> addr
+  (** [address cidr] is the address for [cidr]. *)
+
   val first : t -> addr
   (** [first subnet] is first valid unicast address in this [subnet]. *)