diff --git a/core/forkid/forkid_test.go b/core/forkid/forkid_test.go
index f29b109985c..c2c97de8239 100644
--- a/core/forkid/forkid_test.go
+++ b/core/forkid/forkid_test.go
@@ -135,6 +135,16 @@ func TestCreation(t *testing.T) {
 				{6000000, ID{Hash: checksumToBytes(0xB8C6299D), Next: 0}},       // Future London block
 			},
 		},
+		// Sepolia test cases
+		{
+			params.SepoliaChainConfig,
+			params.SepoliaGenesisHash,
+			[]testcase{
+				{0, ID{Hash: checksumToBytes(0xfe3366e7), Next: 1735371}},       // Unsynced, last Frontier, Homestead, Tangerine, Spurious, Byzantium, Constantinople, Petersburg, Istanbul, Berlin and first London block
+				{1735370, ID{Hash: checksumToBytes(0xfe3366e7), Next: 1735371}}, // Last pre-MergeNetsplit block
+				{1735371, ID{Hash: checksumToBytes(0xb96cbd13), Next: 0}},       // First MergeNetsplit block
+			},
+		},
 	}
 	for i, tt := range tests {
 		for j, ttt := range tt.cases {
diff --git a/params/chainspecs/sepolia.json b/params/chainspecs/sepolia.json
index ec4f7538390..628a7440ded 100644
--- a/params/chainspecs/sepolia.json
+++ b/params/chainspecs/sepolia.json
@@ -15,6 +15,6 @@
   "berlinBlock": 0,
   "londonBlock": 0,
   "terminalTotalDifficulty": 17000000000000000,
-  "terminalBlockHash": "0x0000000000000000000000000000000000000000000000000000000000000000",
+  "mergeNetsplitBlock": 1735371,
   "ethash": {}
 }
diff --git a/params/config.go b/params/config.go
index faf6fa6fa61..200af283c7f 100644
--- a/params/config.go
+++ b/params/config.go
@@ -405,7 +405,7 @@ func (c *ChainConfig) String() string {
 		)
 	}
 
-	return fmt.Sprintf("{ChainID: %v, Homestead: %v, DAO: %v, DAO Support: %v, Tangerine Whistle: %v, Spurious Dragon: %v, Byzantium: %v, Constantinople: %v, Petersburg: %v, Istanbul: %v, Muir Glacier: %v, Berlin: %v, London: %v, Arrow Glacier: %v, Gray Glacier: %v, Terminal Total Difficulty: %v, Engine: %v}",
+	return fmt.Sprintf("{ChainID: %v, Homestead: %v, DAO: %v, DAO Support: %v, Tangerine Whistle: %v, Spurious Dragon: %v, Byzantium: %v, Constantinople: %v, Petersburg: %v, Istanbul: %v, Muir Glacier: %v, Berlin: %v, London: %v, Arrow Glacier: %v, Gray Glacier: %v, Terminal Total Difficulty: %v, Merge Netsplit: %v, Engine: %v}",
 		c.ChainID,
 		c.HomesteadBlock,
 		c.DAOForkBlock,
@@ -422,6 +422,7 @@ func (c *ChainConfig) String() string {
 		c.ArrowGlacierBlock,
 		c.GrayGlacierBlock,
 		c.TerminalTotalDifficulty,
+		c.MergeNetsplitBlock,
 		engine,
 	)
 }
@@ -615,6 +616,7 @@ func (c *ChainConfig) CheckConfigForkOrder() error {
 		{name: "londonBlock", block: c.LondonBlock},
 		{name: "arrowGlacierBlock", block: c.ArrowGlacierBlock, optional: true},
 		{name: "grayGlacierBlock", block: c.GrayGlacierBlock, optional: true},
+		{name: "mergeNetsplitBlock", block: c.MergeNetsplitBlock, optional: true},
 	} {
 		if lastFork.name != "" {
 			// Next one must be higher number