diff --git a/pkg/tcpip/header/checksum.go b/pkg/tcpip/header/checksum.go
index 1cdda6b90..060b4a86c 100644
--- a/pkg/tcpip/header/checksum.go
+++ b/pkg/tcpip/header/checksum.go
@@ -57,6 +57,9 @@ func checksumUpdate2ByteAlignedUint16(xsum, old, new uint16) uint16 {
 	//        checksum C, the new checksum C' is:
 	//
 	//                C' = C + (-m) + m' = C + (m' - m)
+	if old == new {
+		return xsum
+	}
 	return checksum.Combine(xsum, checksum.Combine(new, ^old))
 }
 
diff --git a/pkg/tcpip/header/checksum_test.go b/pkg/tcpip/header/checksum_test.go
index 984508d32..0776f58b1 100644
--- a/pkg/tcpip/header/checksum_test.go
+++ b/pkg/tcpip/header/checksum_test.go
@@ -17,6 +17,7 @@
 package header_test
 
 import (
+	"bytes"
 	"fmt"
 	"math/rand"
 	"sync"
@@ -89,6 +90,24 @@ func TestICMPv4Checksum(t *testing.T) {
 	}, want, fmt.Sprintf("header: {% x} data {% x}", h, b.Flatten()))
 }
 
+func TestICMPv4ChecksumUpdate(t *testing.T) {
+	const icmpIdent = 0
+
+	data := make([]byte, header.ICMPv4MinimumSize)
+	h := header.ICMPv4(data)
+	h.SetType(header.ICMPv4EchoReply)
+	h.SetCode(header.ICMPv4UnusedCode)
+	h.SetIdent(icmpIdent)
+	h.SetChecksum(^checksum.Checksum(data, 0))
+
+	updated := header.ICMPv4(bytes.Clone(data))
+	// Perform an incremental checksum update where we aren't actually changing the ID.
+	updated.SetIdentWithChecksumUpdate(icmpIdent)
+	if updated.Checksum() != h.Checksum() {
+		t.Errorf("got updated.Checksum() = %x, want = %x", updated.Checksum(), h.Checksum())
+	}
+}
+
 func TestICMPv6Checksum(t *testing.T) {
 	rnd := rand.New(rand.NewSource(42))