diff --git a/nucypher/blockchain/eth/clients.py b/nucypher/blockchain/eth/clients.py
index 3897a2bff..24790b5ac 100644
--- a/nucypher/blockchain/eth/clients.py
+++ b/nucypher/blockchain/eth/clients.py
@@ -53,6 +53,7 @@ PUBLIC_CHAINS = {
     77: "Sokol",
     100: "xDai",
     137: "Polygon/Mainnet",
+    11155111: "Sepolia",
     80001: "Polygon/Mumbai"
 }
 
diff --git a/nucypher/blockchain/eth/networks.py b/nucypher/blockchain/eth/networks.py
index 6705226cd..ed9d80cfc 100644
--- a/nucypher/blockchain/eth/networks.py
+++ b/nucypher/blockchain/eth/networks.py
@@ -18,7 +18,7 @@ class NetworksInventory:  # TODO: See #1564
         MAINNET: 1,  # Ethereum Mainnet
         IBEX: 5,  # this is required for configuration file migrations (backwards compatibility)
         LYNX: 5,  # Goerli
-        TAPIR: 5,
+        TAPIR: 11155111,  # Sepolia
         ORYX: 5
     }
     __to_chain_id_polygon = {