HELOC Payment Calculator

Estimate the payment path for a home equity line of credit (HELOC) with this calculator. Enter your home value, mortgage balance, credit line limit, amount drawn, rate, and draw and repayment periods to review estimated equity, combined loan-to-value (CLTV), interest-only payments, repayment payments, and total modeled interest.

## How HELOC draw and repayment periods affect payments

A HELOC usually has a draw period followed by a repayment period. During the draw period, a plan may allow interest-only payments, but you may also be able to pay principal. When the draw period ends, further borrowing typically stops and the outstanding balance must be repaid; required payments may rise substantially. Many HELOCs also have variable rates, so payments may change even if you do not borrow more. The Consumer Financial Protection Bureau explains these features in its HELOC overview; read that guidance and your own plan agreement before borrowing.

## Estimate available equity and CLTV

Home equity is estimated as home value minus the outstanding mortgage balance. The calculator estimates a maximum total debt using your entered CLTV assumption, subtracts the mortgage balance, and compares that amount with your contract line limit. This is a planning estimate only: a lender may use a different appraisal, CLTV limit, credit review, income verification, fees, or line rules.

## Model monthly draws and repayment payments

Set an initial draw and, if useful, an additional monthly draw during the draw period. The estimate applies new draws at the beginning of each modeled month, calculates interest on that month's balance, then models interest-only payments. At the end of the draw period, the projected balance is amortized over the repayment term at the entered rate. The schedule shows draws, payments, principal, interest, and remaining balance. A draw that exceeds the estimated line capacity is capped and flagged.

## Stress-test variable rates and payment shock

Use the rate-change input to compare a rate-increase or rate-decrease scenario. The calculator holds that adjusted rate constant across both modeled phases and applies your entered rate floor and cap; it does not forecast Prime Rate, future resets, lender margins, or contract-specific rate changes. Compare the last draw-period interest payment with the first repayment payment to see an estimated payment change, then download the complete CSV schedule for review.

HELOC interest tax treatment depends on the use of loan proceeds and other requirements. For U.S. taxpayers, the IRS explains that interest may qualify as home mortgage interest when proceeds are used to buy, build, or substantially improve the home securing the debt, subject to applicable limits and rules. Review IRS Publication 936 and consult a qualified tax professional for your situation.

This calculator is an educational estimate, not a loan offer, tax determination, or financial advice. Confirm the actual index, margin, payment formula, minimums, fees, draw rules, rate caps, and repayment schedule in your lender documents.