An integrated circuit is provided with a modular multiplication circuit. The modular multiplication circuit includes an input multiplier for computing the product of two input signals, truncated multipliers for computing another product based on a modulus value and the product, and a subtraction circuit for computing a difference between the two products. An error correction circuit uses the difference to look up an estimated quotient value and to subtract out an integer multiple of the modulus value from the difference in a single step, wherein the integer multiple is equal to the estimated quotient value. A final adjustment stage is used to remove any remaining residual estimation error.