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Car Loan Interest Deduction MAGI Phaseout Explained
How filing status and modified adjusted gross income can reduce the vehicle-loan-interest deduction.
Matthew NewmanAuthor and editorial reviewer · Primary sources checked 2026-08-28A phaseout does not necessarily switch a deduction from fully available to zero at one dollar of income. It usually reduces the amount across a range.
Modified adjusted gross income can differ from the number someone informally calls “income.” Use the definition and figures that apply to the complete federal return.
Start with qualified interest
First identify the interest that meets the vehicle and loan rules, then apply the annual cap. Do not run a phaseout against principal payments or total vehicle cost.
The starting amount should be supported by lender records and the vehicle file.
Use the correct filing status
Thresholds differ by filing status. A preview should never assume that “single” and “married filing jointly” share the same phaseout range.
If filing status is uncertain, compare scenarios but wait for the actual return facts before treating any estimate as final.
Keep the preview in context
A planning estimate is useful for spotting missing inputs and preparing questions. It is not a refund estimate and does not account for every part of a tax return.
Recheck IRS guidance for the filing year and ask a qualified tax professional to review the completed calculation.
Authoritative sources
Sources were last reviewed on . We prefer primary government and platform documentation, link claims to their source, and recheck articles when rules or app behavior changes. Always verify the source for the relevant year or situation.