Your employers each think they're your only job.
Estimate Tax Liability shows you the gap. The Benefits Optimizer makes sure you're not leaving money on the table.
Withholding Gap
-$28,293
W-4 adjustments needed for 3 employers
Uncaptured Match
$3,200/yr
Optimize contributions across 3 plans
Know your withholding gap before April does
Enter your pay stub numbers every two weeks. Estimate Tax Liability projects your year-end federal tax, compares it to what's being withheld, and tells you exactly how to adjust each employer's W-4.
- Year-end federal tax projection from pay stub data
- Per-employer W-4 adjustment recommendations
- Quarterly estimated payment schedule
- Prior-year W2 safe harbor analysis
“I check it every two weeks when my pay stub lands. Takes 2 minutes. I know exactly where I stand.”
“Last year I over-withheld by $4,200. That's $4,200 earning 0% at the IRS for 14 months. Never again.”
W-4 adjustments per employer
Free vs Pro
| Feature | Free | Pro |
|---|---|---|
| Year-end projection | ±15% range | |
| W-4 adjustments | — | |
| Quarterly payments | — | |
| Prior-year W2 analysis | — |
Capture every dollar of employer match
Most multi-W2 professionals max out one 401(k) and ignore the rest. The Benefits Optimizer maps every employer's match formula, finds the optimal contribution split, and tells you the per-paycheck amounts.
- Side-by-side comparison of every employer plan
- Optimal contribution allocation per paycheck
- HSA eligibility and mega backdoor detection
- Overlap warnings when plans conflict
“I didn't even know the startup had a non-elective contribution. Free money I was leaving on the table for 8 months.”
“$3,200 a year in employer match I wasn't capturing. That's more than the Pro subscription costs in a decade.”
Tech Corp
100% match up to 6%
Consulting LLC
50% match up to 8%
Startup Inc
3% non-elective
Max Tech Corp first (highest match rate), then Consulting LLC
The average multi-W2 professional leaves $2,800/year in uncaptured employer match
It's not that they don't know about 401(k) matching — it's that they max out one plan and forget the rest. Different match formulas, different vesting schedules, different plan years. The Benefits Optimizer cuts through the complexity and shows you exactly where to put each dollar.
The difference is measurable
Before MultiW2
- Guessing withholding is "probably close enough"
- Over-withholding by thousands — lending the IRS money at 0%
- Maxing one 401(k), ignoring the other two
- Scrambling to find cash for a surprise April bill
- Paying a CPA $400/hr to tell you what a spreadsheet could
After 6 months of Pro
- Exact withholding gap updated every pay period
- W-4 adjustments dialed in across all employers
- Employer match captured from every plan
- Quarterly estimates calculated — no April surprises
- CPA time cut to review, not research
Annual ROI
Start free. Upgrade when the ±15% range isn't enough.
Free users get year-end projections as ranges. Pro users get exact numbers, per-employer W-4 adjustments, safe harbor analysis, and full benefits optimization.