diff --git a/execution/gethexec/sequencer.go b/execution/gethexec/sequencer.go
index e1deadf60f..b0c9e6821f 100644
--- a/execution/gethexec/sequencer.go
+++ b/execution/gethexec/sequencer.go
@@ -1565,6 +1565,7 @@ func (s *Sequencer) updateExpectedSurplus(ctx context.Context) (int64, error) {
 			} else {
 				// l1GasPrice can be zero because of roundings, hence backlogCost is calculated separately
 				backlogFee := big.NewInt(backlogCallDataUnits)
+				backlogFee.Mul(backlogFee, blobFeePerByte)
 				backlogFee.Mul(backlogFee, blobTxBlobGasPerBlob)
 				backlogFee.Div(backlogFee, usableBytesInBlob)
 				backlogCost = backlogFee.Int64() / 16