diff --git a/config/mainnet.chain.yml b/config/mainnet.chain.yml
index 78228609..d11f59b4 100644
--- a/config/mainnet.chain.yml
+++ b/config/mainnet.chain.yml
@@ -49,7 +49,7 @@ CAPELLA_FORK_VERSION: 0x03000000
 CAPELLA_FORK_EPOCH: 194048  # April 12, 2023, 10:27:35pm UTC
 # Deneb
 DENEB_FORK_VERSION: 0x04000000
-DENEB_FORK_EPOCH: 18446744073709551615
+DENEB_FORK_EPOCH: 269568  # March 13, 2024, 01:55:35pm UTC
 # EIP6110
 EIP6110_FORK_VERSION: 0x05000000  # temporary stub
 EIP6110_FORK_EPOCH: 18446744073709551615