diff --git a/core/tx_list.go b/core/tx_list.go
index 2935929d72..838433b897 100644
--- a/core/tx_list.go
+++ b/core/tx_list.go
@@ -254,7 +254,10 @@ func (l *txList) Add(tx *types.Transaction, priceBump uint64) (bool, *types.Tran
 	old := l.txs.Get(tx.Nonce())
 	if old != nil {
 		threshold := new(big.Int).Div(new(big.Int).Mul(old.GasPrice(), big.NewInt(100+int64(priceBump))), big.NewInt(100))
-		if threshold.Cmp(tx.GasPrice()) >= 0 {
+		// Have to ensure that the new gas price is higher than the old gas
+		// price as well as checking the percentage threshold to ensure that
+		// this is accurate for low (Wei-level) gas price replacements
+		if old.GasPrice().Cmp(tx.GasPrice()) >= 0 || threshold.Cmp(tx.GasPrice()) > 0 {
 			return false, nil
 		}
 	}