We have found that the best way to make payments to the IRS and states, for personal Form 1040 amounts due with returns or estimated tax payments, is through their online system. The payments are completely traceable and it is then much easier to remember all that you paid, when preparing your return in April. Below are the links to the federal system and the states we find most popular. We encourage you to sign up on these sites now so you can make the necessary payments when the time comes. These cannot be used without prior registration.
If previously registered for EFTPS: https://www.eftps.com/eftps/login/loginInitial
If not registered anywhere, retrieve payments at https://www.irs.gov/individuals/get-transcript and click Request Online