diff --git a/sdk/program/src/pubkey.rs b/sdk/program/src/pubkey.rs
index f31579fd4f..a8992c3672 100644
--- a/sdk/program/src/pubkey.rs
+++ b/sdk/program/src/pubkey.rs
@@ -176,7 +176,9 @@ impl Pubkey {
 
         let mut b = [0u8; 32];
         let i = I.fetch_add(1);
-        b[0..8].copy_from_slice(&i.to_le_bytes());
+        // use big endian representation to ensure that recent unique pubkeys
+        // are always greater than less recent unique pubkeys
+        b[0..8].copy_from_slice(&i.to_be_bytes());
         Self::new(&b)
     }