Today is the deadline for filing your 2015 personal income tax return or an extension for it (it’s tomorrow if you’re in Maine or Massachusetts). It’s also the deadline for filing Form 1065 for partnerships (including LLCs that file as such) as well as Schedule K-1s for owners. And it’s the due date for the first installment of 2016 estimated taxes. Even if you get a filing extension, this doesn’t give you more time to make your estimated tax payment. Use EFTPS.gov to make tax payments electronically (there’s no government fee for using this service).