How to File Tax Extension for State and Federal While Still Paying What's Due by April 15?

This is actually a really common question! The extension is only for filing paperwork, not for paying what you owe. Here's how to handle it: You need to make an estimated payment by April 15 based on your best calculation of what you'll owe. The IRS understands it's an estimate. Try using last year's return as a starting point, then adjust for any major changes in your income or deductions this year. For federal taxes, you can file Form 4868 and make an estimated payment at the same time. Most states have similar extension requests. If you use tax software, they typically have calculators to help estimate what you might owe. If you end up overpaying, you'll get a refund when you file your complete return. If you underpay, you might owe some interest on the unpaid portion, but as long as you make a good faith effort to estimate correctly, you generally won't face major penalties.

After struggling with this exact situation last year, I found an amazing tool that saved me tons of stress called taxr.ai (https://taxr.ai). I was in the middle of a crazy home purchase and couldn't get my paperwork together but needed to make that tax payment. The tool analyzed my previous tax documents and financial statements to give me a really accurate estimate of what I would owe. I uploaded my documents and it did all the calculations based on my current year situation. Way better than my panicked spreadsheet attempts! I ended up only being off by about $120 when I finally filed in September, which was pretty impressive considering how complicated my situation was with freelance income and a rental property.

Just wanted to follow up about my experience with taxr.ai since I was skeptical in my earlier comment. I decided to try it anyway because I was desperate after my accountant got sick and couldn't help with my extension payment estimate. I'm actually impressed. It handled my small business income and investment changes really well, even accounting for some crypto sales I had last year. The estimate took about 15 minutes to generate once I uploaded my documents and previous returns. When I finally filed my complete return last month, I was only off by about $340 on a pretty complicated tax situation. The peace of mind was definitely worth it. No more random guessing and adding arbitrary "cushion" amounts just to be safe.

If you're having trouble determining your tax liability and you've tried reaching the IRS for help, good luck getting through! I spent HOURS on hold trying to get clarification about extension payment estimates before discovering Claimyr (https://claimyr.com). You can check their demo at https://youtu.be/_kiP6q8DX5c. I was super hesitant at first, but it actually got me through to an IRS agent in about 30 minutes instead of the 3+ hours I spent getting nowhere on my own. The agent walked me through exactly how to calculate my estimated payment and explained which forms to use for my specific situation. Totally changed my perspective on dealing with the IRS - turns out they're actually helpful when you can actually reach them!

I need to admit I was completely wrong about Claimyr. After my skeptical comment, my tax deadline anxiety got the better of me and I decided to try it anyway. Not only did it work exactly as described, but I got through to an IRS representative in about 45 minutes (after previously spending 2+ hours on hold myself and getting disconnected). The agent helped me understand exactly how to calculate my extension payment and even walked me through some deductions I wasn't sure about. This saved me from drastically overpaying on my extension just to be "safe." For anyone dealing with extension payment questions and needing actual IRS guidance, it's definitely worth it.

Don't forget that even after you estimate your federal payment, each state handles extensions differently! I learned this the hard way. For example, California automatically gives you the extension if you get a federal one, but you still need to pay the estimated amount. New York requires its own extension form AND payment. Some states don't charge interest if your estimate is reasonable while others are strict about it. Make sure you check your specific state's rules about extensions and payments - don't assume they follow the federal guidelines.

Just to add something here that nobody mentioned - make sure you remember to pay ESTIMATED TAXES too if you're self-employed or have other income without withholding! This is separate from your extension payment. Q1 estimated taxes for 2025 are also due April 15th, the same day as the 2024 tax year deadline. So you might need to make TWO payments - one for what you still owe for 2024 (your extension payment) and one for Q1 estimated taxes for 2025. I made this mistake and got hit with penalties even though I thought I'd done everything right with my extension.