Technically you CAN have more than one codicil but it's not wise if you believe your estate might be contested by one of the beneficiaries. Each and every codicil adds more leeway for misinterpretation of your actual intentions. If you execute two codicils that both change the beneficiaries of your estate, chances are at least one beneficiary is going to contest the first codicil, the second one, or both. When in doubt, it's best to create a new will. In it you should reference the original will and state that it is now null and void.