WithholdWise

WithholdWise helps W-2 employees with side income (or variable bonuses/RSUs) stop getting hit with underpayment penalties and big April balances. Instead of focusing on quarterly payments, it calculates the simplest path: adjust W-4 withholding (or add an extra per-paycheck amount) to cover estimated tax needs automatically. Users connect payroll (or upload paystubs), import last year’s return summary, and link income sources like 1099 platforms. The app projects year-end tax, checks safe-harbor thresholds, and generates a step-by-step W-4 recommendation with a plain-English explanation of tradeoffs (cash flow vs. refund). It also monitors changes (new job, bonus, RSU vest, side gig spike) and alerts when the plan is drifting. This is a web app + mobile companion, combining traditional rules-based tax logic with light AI for document parsing and explanations.