best tax planning software for roth conversions: Complete 2026 Guide

If you are searching for the best tax planning software for roth conversions, you are solving a margin problem, not a calculator problem. A basic tool can show this year tax cost. A strong tool helps you decide whether paying tax now creates a better lifetime outcome after considering IRS brackets, Social Security taxation, Medicare IRMAA thresholds, state taxes, and account withdrawal sequencing.

Most families should run Roth conversion planning as an annual process, not a one-time event. Before you choose software, get context on your broader tax playbook in the Tax Strategies hub, then pair conversion planning with deduction planning using Best Tax Deductions 2025 and Best Tax Deductions for High Income Earners.

best tax planning software for roth conversions: what actually determines value

Good Roth software does not just show a pretty before-and-after chart. It should support real decisions you can execute with a CPA.

Use this practical test:

• It models marginal and effective tax rates by year, not just one blended tax estimate.
• It supports multi-year conversion ladders, including bracket-fill logic.
• It handles Social Security interaction rules from the IRS framework for provisional income.
• It reflects Medicare IRMAA cliffs used by CMS, so you can avoid hidden premium spikes.
• It shows where conversion tax is paid from, because paying tax from taxable cash versus IRA assets changes outcomes.
• It lets you compare scenarios side by side with explicit assumptions and sensitivity ranges.

Real-world planners in CFP communities and Bogleheads discussions consistently point to this issue: the conversion amount is less important than the assumptions behind it. A recommendation to convert at 22% can be smart or expensive depending on expected RMD pressure, surviving spouse bracket risk, and whether your state taxes retirement income.

Decision Framework: Pick Software by Decision Risk, Not by Dashboard Design

Score each tool on a 100-point scale before buying:

• 30 points: tax engine quality and bracket detail.
• 20 points: multi-year planning depth.
• 15 points: Social Security and IRMAA modeling.
• 10 points: cash-source tax payment modeling.
• 10 points: scenario comparison and sensitivity testing.
• 10 points: integration with your current workflow.
• 5 points: export quality for CPA handoff.

Interpretation:

• 85 to 100: strong fit for complex Roth conversion planning.
• 70 to 84: usable for many households with CPA review.
• Below 70: high risk of over-converting or under-converting.

Scenario Table: Match Software to Your Conversion Problem

Software Categories and Practical Picks for 2026

Advisor-suite planners for households needing ongoing guidance

Advisor-oriented suites are best when your plan has many moving parts, such as business income, trust distributions, pension choices, and multiple account types. In CFP circles, eMoney is often mentioned for client-facing scenario work, especially when a household has mixed taxable and pre-tax assets and needs repeatable annual updates.

Best for:

• Complex household cash flows.
• Ongoing advisor collaboration.
• Families that want one plan spanning tax, retirement, and estate assumptions.

Watch-outs:

• Cost can be high for direct-to-consumer access.
• Some advisor tools are strong on planning visuals but weaker on granular tax assumptions unless configured carefully.

Advanced DIY retirement planners for self-directed households

Bogleheads discussions frequently compare Boldin, MaxiFi, and Pralana for conversion analysis. The common lesson is useful: no tool should be trusted from a default recommendation alone. You must inspect assumptions, especially future tax regime, return assumptions, and spending path.

Best for:

• DIY investors willing to verify assumptions.
• Couples running multiple what-if scenarios each year.
• Households focused on lifetime after-tax spending power.

Watch-outs:

• Inputs take time to set up correctly.
• Recommendation quality drops sharply if account balances, basis, or income timing is outdated.

Specialized Roth conversion calculators for focused what-if work

Niche tools, including ImagiSOFT style Roth conversion calculators, can be effective for targeted analysis of conversion size and tax tradeoffs. They are often faster for one decision than full planning suites.

Best for:

• Narrow conversion questions.
• Advisors who already have separate systems for full financial planning.

Watch-outs:

• Limited integration with broader retirement and estate planning assumptions.
• Can miss second-order effects like IRMAA or survivor tax brackets if not modeled elsewhere.

Spreadsheet plus CPA projection as a baseline alternative

A spreadsheet plus CPA-prepared tax projection can be enough for simple cases. It is often cheaper but requires discipline.

Best for:

• Straightforward tax situations.
• Households comfortable with manual updates.

Watch-outs:

• High error risk under changing assumptions.
• Weak scenario management and poor repeatability year to year.

Fully Worked Numeric Example: Early Retiree Bracket-Fill Strategy

Assumptions for illustration only:

• Filing status: married filing jointly.
• Ages: 58 and 56.
• Traditional IRA balance: 1,200,000.
• Taxable brokerage: 320,000.
• Current Roth balance: 0.
• Ordinary income before conversion: 35,000.
• Standard deduction assumption: 32,000.
• Target taxable ordinary income ceiling assumption: 100,000.
• Federal tax focus only, state tax excluded for clarity.
• Long-term annual return assumption: 6.5%.

Step 1: Find baseline taxable ordinary income.

35,000 ordinary income minus 32,000 deduction equals 3,000 taxable ordinary income before conversion.

Step 2: Estimate bracket-fill room.

Target ceiling 100,000 minus 3,000 baseline equals 97,000 of potential conversion room. Household chooses 95,000 for buffer.

Step 3: Estimate incremental federal tax for the conversion.

Illustrative tax math:

• Tax before conversion on 3,000 is about 300.
• Tax after conversion on 98,000 taxable ordinary income is about 11,300.
• Incremental tax from conversion is roughly 11,000.

Effective tax rate on conversion:

11,000 divided by 95,000 equals about 11.6%.

Step 4: Project multi-year impact.

Assume they repeat 95,000 conversion for 8 years:

Step 5: Add growth comparison over 10 years after full conversion period.

• 760,000 growing at 6.5% for 10 years is about 1,430,000 inside Roth.
• If still in traditional and taxed at 24% at withdrawal, after-tax value is about 1,087,000.
• Difference is roughly 343,000 before considering the opportunity cost of paying taxes from taxable assets.

Tradeoffs to evaluate:

• If 88,000 tax paid from brokerage would have compounded at 5%, opportunity cost is about 55,000 over 10 years.
• Net benefit still remains substantial in this scenario, but shrinks if future withdrawal rate is lower than expected.
• Add state tax to both sides before final decision.

This is why software matters. You need scenario A versus scenario B with explicit assumptions, not one headline recommendation.

Step-by-Step Implementation Plan

1. Export current balances for all taxable, tax-deferred, and Roth accounts.
2. Pull last two tax returns and identify ordinary income, capital gains, credits, and carryforwards.
3. Build a baseline current-year projection with no conversion.
4. Define conversion guardrails: target bracket, IRMAA ceiling, and minimum cash reserve.
5. Run at least three conversion scenarios: conservative, base case, aggressive.
6. Evaluate tax payment source options and avoid unnecessary IRA tax withholding.
7. Select target conversion amount with a documented reason and fallback amount.
8. Send projection summary to CPA for validation before execution.
9. Execute conversion early enough to leave correction time before year end.
10. Re-run projection in November or early December and adjust if income changed.

If your income profile is W-2 heavy, pair conversion modeling with deduction planning from Best Tax Deductions for W-2 Employees. If self-employed, pair it with Best Tax Deductions for Self-Employed to open lower-tax conversion windows.

30-Day Checklist to Execute Your First Optimized Conversion Cycle

• [ ] Day 1-3: Gather account statements and prior two tax returns.
• [ ] Day 1-3: Confirm filing status, dependents, and expected annual income.
• [ ] Day 4-7: Enter baseline assumptions into your planning software.
• [ ] Day 4-7: Validate deduction assumptions and capital gain estimates.
• [ ] Day 8-10: Run no-conversion baseline and save it as Scenario 0.
• [ ] Day 8-10: Run three conversion amounts and compare marginal rates.
• [ ] Day 11-14: Check Social Security and Medicare implications for future years.
• [ ] Day 11-14: Stress test state tax assumptions and possible relocation timing.
• [ ] Day 15-18: Decide tax payment source and maintain liquidity buffer.
• [ ] Day 15-18: Draft CPA review packet with assumptions and outputs.
• [ ] Day 19-22: CPA review and adjustment round.
• [ ] Day 23-25: Finalize target conversion amount and backup amount.
• [ ] Day 26-28: Execute conversion with custodian and record confirmations.
• [ ] Day 29-30: Update tracker for next year, including lessons learned.

Common Mistakes That Cost Real Money

• Converting based on average tax rate instead of marginal tax rate.
• Ignoring IRMAA thresholds and creating avoidable Medicare premium surcharges.
• Using stale income assumptions from last year instead of current-year reality.
• Failing to model surviving spouse tax brackets after first death.
• Paying conversion tax from IRA dollars when taxable cash is available.
• Treating one software recommendation as final without sensitivity testing.
• Running only one-year analysis and missing multi-year opportunity cost.
• Ignoring state-tax timing when a move is likely in the next few years.
• Skipping CPA coordination and discovering filing issues after execution.
• Waiting until late December and losing flexibility when income changes.

A practical rule: if your model does not show what happens under at least three tax-rate futures, you are not really planning yet.

How This Compares To Alternatives

For commercial intent buyers, the key decision is not feature count. It is whether the tool improves the quality of decisions you actually implement.

When Not to Use This Strategy

Roth conversion software-driven planning is powerful, but not always the top priority. Consider pausing or reducing conversions when:

• You cannot pay conversion tax from cash without weakening your safety reserve.
• You expect clearly lower marginal rates later due to temporary current income spikes.
• You are near ACA subsidy cliffs and higher MAGI would reduce subsidies materially.
• You plan to relocate from a high-tax to low-tax state soon.
• You have high-interest debt that likely offers a better guaranteed return if paid off first.
• You need IRA assets for near-term spending and conversion creates liquidity pressure.
• Your planning assumptions are too uncertain to support a confident multi-year path.

Questions to Ask Your CPA/Advisor

1. What marginal bracket should we target this year, and what is the exact guardrail amount?
2. How will this conversion affect next-year Medicare premiums under IRMAA rules?
3. Do we expect Social Security taxability to increase because of this conversion path?
4. Should we pay estimated taxes quarterly or increase withholding elsewhere?
5. What state-tax effects should we model now versus after a potential move?
6. How does this plan change if one spouse dies first and filing status changes?
7. What return assumptions are reasonable for sensitivity testing?
8. What is our no-conversion baseline lifetime tax estimate?
9. Which assumptions in our software output are most fragile?
10. What documentation should we keep for clean filing and future review?

Bottom Line

The best tax planning software for Roth conversions is the tool that helps you make better yearly decisions under uncertainty, then execute those decisions with CPA validation. Start with a scorecard, run multi-year bracket-fill scenarios, and avoid one-click recommendations.

Use the blog for deeper tax strategy examples, and review implementation options in programs. This content is educational and should be paired with professional tax advice for your specific facts.