diff --git a/pkg/core/native/native_gas.go b/pkg/core/native/native_gas.go
index 2903e10f9..e06925741 100644
--- a/pkg/core/native/native_gas.go
+++ b/pkg/core/native/native_gas.go
@@ -54,7 +54,7 @@ func (g *GAS) increaseBalance(_ *interop.Context, _ util.Uint160, si *state.Stor
 			err = errors.New("insufficient funds")
 		}
 		return err
-	} else if sign == -1 && acc.Balance.Cmp(new(big.Int).Neg(amount)) == -1 {
+	} else if sign == -1 && acc.Balance.CmpAbs(amount) == -1 {
 		return errors.New("insufficient funds")
 	}
 	acc.Balance.Add(&acc.Balance, amount)
diff --git a/pkg/core/native/native_neo.go b/pkg/core/native/native_neo.go
index eb5291d87..163525080 100644
--- a/pkg/core/native/native_neo.go
+++ b/pkg/core/native/native_neo.go
@@ -405,7 +405,7 @@ func (n *NEO) increaseBalance(ic *interop.Context, h util.Uint160, si *state.Sto
 	if err != nil {
 		return err
 	}
-	if (amount.Sign() == -1 && acc.Balance.Cmp(new(big.Int).Neg(amount)) == -1) ||
+	if (amount.Sign() == -1 && acc.Balance.CmpAbs(amount) == -1) ||
 		(amount.Sign() == 0 && checkBal != nil && acc.Balance.Cmp(checkBal) == -1) {
 		return errors.New("insufficient funds")
 	}