diff --git a/src/Nethermind/Nethermind.Taiko.Test/L1OriginStoreTests.cs b/src/Nethermind/Nethermind.Taiko.Test/L1OriginStoreTests.cs
index 954bfacd3082..4c0870ecc5e9 100644
--- a/src/Nethermind/Nethermind.Taiko.Test/L1OriginStoreTests.cs
+++ b/src/Nethermind/Nethermind.Taiko.Test/L1OriginStoreTests.cs
@@ -202,5 +202,23 @@ public void Fails_for_invalid_length_signature(int signatureLength)
         Action act = () => _decoder.Encode(origin);
         act.Should().Throw<RlpException>().WithMessage($"*Signature*{L1OriginDecoder.SignatureLength}*");
     }
+
+    [Test]
+    public void Encode_produces_RLP_with_correct_sequence_length(
+        [Values(false, true)] bool withBuildPayload,
+        [Values(false, true)] bool withForcedInclusion,
+        [Values(false, true)] bool withSignature)
+    {
+        int[]? buildPayloadArgsId = withBuildPayload ? Enumerable.Range(0, 8).ToArray() : null;
+        int[]? signature = withSignature ? Enumerable.Range(0, 65).ToArray() : null;
+        L1Origin origin = new(123, Hash256.Zero, 456, Hash256.Zero, buildPayloadArgsId, withForcedInclusion, signature);
+
+        Rlp encoded = _decoder.Encode(origin);
+        RlpStream stream = new(encoded.Bytes);
+        (int prefixLength, int contentLength) = stream.ReadPrefixAndContentLength();
+
+        contentLength.Should().Be(encoded.Bytes.Length - prefixLength,
+            "StartSequence must receive content length, not total length");
+    }
 }
 
diff --git a/src/Nethermind/Nethermind.Taiko/L1OriginDecoder.cs b/src/Nethermind/Nethermind.Taiko/L1OriginDecoder.cs
index 9e57c56f940a..329a766b3b7a 100644
--- a/src/Nethermind/Nethermind.Taiko/L1OriginDecoder.cs
+++ b/src/Nethermind/Nethermind.Taiko/L1OriginDecoder.cs
@@ -49,7 +49,7 @@ public Rlp Encode(L1Origin? item, RlpBehaviors rlpBehaviors = RlpBehaviors.None)
 
     public override void Encode(RlpStream stream, L1Origin item, RlpBehaviors rlpBehaviors = RlpBehaviors.None)
     {
-        stream.StartSequence(GetLength(item, rlpBehaviors));
+        stream.StartSequence(GetContentLength(item, rlpBehaviors));
 
         stream.Encode(item.BlockId);
         stream.Encode(item.L2BlockHash);
@@ -92,6 +92,11 @@ public override void Encode(RlpStream stream, L1Origin item, RlpBehaviors rlpBeh
     }
 
     public override int GetLength(L1Origin item, RlpBehaviors rlpBehaviors)
+    {
+        return Rlp.LengthOfSequence(GetContentLength(item, rlpBehaviors));
+    }
+
+    private int GetContentLength(L1Origin item, RlpBehaviors rlpBehaviors)
     {
         int buildPayloadLength = 0;
         if (item.BuildPayloadArgsId is not null || item.IsForcedInclusion || item.Signature is not null)
@@ -107,14 +112,12 @@ public override int GetLength(L1Origin item, RlpBehaviors rlpBehaviors)
             isForcedInclusionLength = Rlp.LengthOf(item.IsForcedInclusion);
         }
 
-        return Rlp.LengthOfSequence(
-            Rlp.LengthOf(item.BlockId)
+        return Rlp.LengthOf(item.BlockId)
             + Rlp.LengthOf(item.L2BlockHash)
             + Rlp.LengthOf(item.L1BlockHeight ?? 0)
             + Rlp.LengthOf(item.L1BlockHash)
             + buildPayloadLength
             + isForcedInclusionLength
-            + (item.Signature is null ? 0 : Rlp.LengthOfByteString(SignatureLength, 0))
-        );
+            + (item.Signature is null ? 0 : Rlp.LengthOfByteString(SignatureLength, 0));
     }
 }