diff --git a/README.agda b/README.agda
index ced0f11596..cc436d0848 100644
--- a/README.agda
+++ b/README.agda
@@ -19,7 +19,7 @@ module README where
 -- and other anonymous contributors.
 ------------------------------------------------------------------------
 
--- This version of the library has been tested using Agda 2.6.3.
+-- This version of the library has been tested using Agda 2.6.4.
 
 -- The library comes with a .agda-lib file, for use with the library
 -- management system.