Methodology

RothOrTraditional.com compares two complete savings strategies using the same after-tax out-of-pocket budget each year. For Traditional IRAs, we solve for the largest contribution such that contribution minus tax savings from deductible amounts does not exceed your budget. Remaining cash—including tax savings—is invested in a taxable brokerage account with modeled dividend and capital gains taxes.

Tax rules baseline

Eligibility and contribution limits use tax year 2026 configuration with IRS phaseout ranges and aggregate Roth/Traditional limits (including age 50+ catch-up).

What we do not model (v1)

• Roth conversion strategies and backdoor Roth mechanics
• Social Security, Medicare IRMAA, credits, and full state tax codes
• Required minimum distributions and withdrawal sequencing
• Early withdrawal penalties and most exceptions

Retirement withdrawal taxation uses your assumed blended incremental rate—not a full future Form 1040 simulation.

Sources

• https://www.irs.gov/publications/p590a
• https://www.irs.gov/publications/p590b
• https://www.irs.gov/retirement-plans/plan-participant-employee/retirement-topics-ira-contribution-limits
• https://www.irs.gov/retirement-plans/traditional-and-roth-irs
• https://www.irs.gov/forms-pubs/about-form-8606

Last verified: 2026-10-15