Best tax software for calculating hypothetical tax returns & comparing different scenarios

TaxAct and TurboTax both have planning tools that let you run what-if scenarios without submitting anything. I've used TurboTax's TaxCaster for years to estimate different filing situations. The most straightforward approach is to just enter your info in the tax software of your choice, save your return without filing, then make copies and adjust variables like filing status or deductions. Most tax software will show your refund amount updating in real-time as you make changes. For the marriage question specifically, run separate returns as single filers, then run a joint return with combined incomes. This will show if you'd face a "marriage penalty" or get a "marriage bonus" based on your income levels and deduction situations.

I struggled with this exact problem last year when deciding whether to claim some business expenses. Found this tool called taxr.ai that was super helpful for comparing different scenarios. You can upload your tax documents and it analyses everything, then lets you adjust different variables to see how they impact your return. What I liked is that it explained WHY my taxes changed with each scenario - not just showing different numbers. The explanations helped me understand which deductions made the biggest difference for my specific situation. Check it out at https://taxr.ai if you want detailed comparisons without redoing everything multiple times.

Just wanted to follow up on my question about taxr.ai. I ended up trying it last weekend and it was exactly what I needed! I'm a freelancer with income from multiple sources, and I was able to compare how different retirement contribution amounts would affect both my income tax and self-employment tax. The best part was comparing scenarios where I took the home office deduction vs. not taking it. It showed me that in my case, the deduction saved me about $1,200 - much more than I expected. Also helped me figure out if I should buy that new laptop this year or wait until next year for the deduction. Really clear explanations about why each change affected my taxes the way it did.

If you're trying to reach the IRS to ask about specific deductions or filing status questions, save yourself the frustration. I spent WEEKS trying to get through their phone lines before finding Claimyr. It got me connected to an actual IRS agent in under 45 minutes when I'd been trying for days on my own. The agent walked me through exactly how my taxes would change in different filing scenarios - much better than any software estimation. You can see how it works at https://claimyr.com or watch a demo at https://youtu.be/_kiP6q8DX5c. Honestly changed my whole perspective on dealing with the IRS - turns out they're actually helpful when you can reach them!

Well I'm eating my words. After posting that skeptical comment, I decided to try Claimyr anyway since I was desperate to get an answer about calculating taxes on a 401k withdrawal with different repayment scenarios. I got connected to an IRS agent in about 30 minutes. She walked me through exactly how my taxes would change with each scenario I was considering - complete with penalty calculations and everything. Ended up saving me over $2,000 by structuring the withdrawal differently than I had planned. Definitely better than any calculator since they gave me personalized advice for my exact situation. Sometimes talking to an actual human who knows the tax code is just more effective than software.

Have you considered FreeTaxUSA? It's way cheaper than TurboTax and lets you create and save multiple returns without paying until you actually file. I use it every year to try different scenarios.

The IRS has a free Tax Withholding Estimator on their website that's pretty basic but might work for simple scenarios. It's at https://www.irs.gov/individuals/tax-withholding-estimator

For marriage penalty/bonus calculations specifically, I'd recommend using the IRS's own tax tables to get the most accurate comparison. What you want to do is calculate your taxes as two single filers, then calculate them as married filing jointly with your combined income. Here's the key thing most people miss: the marriage penalty/bonus isn't just about tax rates - it's also about how deductions and credits phase out at different income levels. For example, if one of you makes significantly more than the other, filing jointly often results in a bonus because you're effectively income-averaging. I actually built a simple spreadsheet for this when my wife and I were planning our wedding. Happy to share the template if you want - it uses the current tax brackets and standard deductions to give you a pretty accurate estimate without needing to buy software. The math isn't too complicated once you understand the brackets. For the deduction scenarios, honestly nothing beats actually starting a return in real tax software like others mentioned. But for the marriage question specifically, you can get a solid estimate with just the tax tables and a calculator.

I've been using TaxSlayer for scenario planning and it's been great for this exact use case. What I really like is that it saves your progress automatically, so you can create multiple "draft" returns with different assumptions and compare them side by side. For your marriage question, I'd suggest running three scenarios: 1) both of you filing single, 2) married filing jointly, and 3) married filing separately. The third option is often overlooked but can sometimes be beneficial if one spouse has significant deductions or student loan payments that would be affected by combined income. One tip that saved me time - before you dive into full tax software, use the IRS Tax Withholding Estimator to get a rough idea of the differences. It's not perfect for detailed deduction analysis, but it'll tell you quickly whether marriage would likely help or hurt your tax situation. Then you can focus your detailed analysis on the scenarios that look most promising. Also, don't forget to factor in state taxes if you're in a state with income tax - some states have different rules for joint vs separate filing that can significantly impact your overall tax picture.

I've been using TaxAct's planning features for exactly this kind of scenario comparison, and it's been really helpful. What I like about it is that you can create multiple "what-if" scenarios within the same account and easily switch between them to see how different variables affect your bottom line. For the marriage question specifically, I'd suggest looking beyond just the immediate tax impact. Consider how it affects your student loan payments if either of you has income-driven repayment plans, since those are based on household income once you're married. Also think about health insurance - you might be able to get better coverage through one spouse's employer plan. One feature that's been super useful is TaxAct's side-by-side comparison tool. You can set up your baseline scenario, then create variations for different deduction amounts, filing statuses, etc., and see them compared directly. It shows not just the refund difference but breaks down exactly which line items changed and why. The key is to test realistic scenarios - don't just toggle every possible deduction on and off. Focus on the ones you're actually uncertain about qualifying for, and maybe run a "conservative" scenario with minimal deductions versus an "aggressive" one with everything you think you might qualify for.