diff --git a/configs/mainnet.yaml b/configs/mainnet.yaml
index d31634958..317daa1a4 100644
--- a/configs/mainnet.yaml
+++ b/configs/mainnet.yaml
@@ -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
diff --git a/specs/deneb/fork.md b/specs/deneb/fork.md
index 9c314052b..17af2b15c 100644
--- a/specs/deneb/fork.md
+++ b/specs/deneb/fork.md
@@ -29,7 +29,7 @@ Warning: this configuration is not definitive.
 | Name | Value |
 | - | - |
 | `DENEB_FORK_VERSION` | `Version('0x04000000')` |
-| `DENEB_FORK_EPOCH` | `Epoch(18446744073709551615)` **TBD** |
+| `DENEB_FORK_EPOCH` | `Epoch(269568)` (March 13, 2024, 01:55:35pm UTC) |
 
 ## Helper functions