300k mortgage: what is the payment?
Type your interest rate. The 300k mortgage calculator gives the monthly principal and interest on a $300,000 loan over 30 years, the total interest, and the payment over 15 and 20 years. Change the amount or the term to compare other loans.
- Monthly payment
- $1,896.20
A 30-year loan of $300,000.00 at 6.5% costs $1,896.20 a month, with $382,633.47 of interest in total.
- Loan amount
- $300,000.00
- Total interest
- $382,633.47
- Total of payments
- $682,633.47
- Payment over 15 years
- $2,613.32
- Payment over 20 years
- $2,236.72
- Payment over 30 years
- $1,896.20
Monthly payment: $1,896.20. A 30-year loan of $300,000.00 at 6.5% costs $1,896.20 a month, with $382,633.47 of interest in total.
How much of what you pay is interest?
The results are estimates for information only. They are not financial, tax, or legal advice. Check the numbers with your lender or a qualified professional before you decide. Terms of use
How to calculate
Works out the monthly payment and total interest on a $300,000 mortgage at your rate over 30 years or any term, with the payments over 15, 20 and 30 years side by side.
Example with the default inputs (Loan amount $300,000.00, Interest rate 6.5%, Loan term (years) 30): A 30-year loan of $300,000.00 at 6.5% costs $1,896.20 a month, with $382,633.47 of interest in total.
Method: Monthly rate r = yearly rate ÷ 1,200 and n = years × 12 payments. Payment M = L × r ÷ (1 − (1 + r)^−n), or L ÷ n at 0%. Total interest = M × n − L.
- A fixed rate for the whole term, monthly payments, and no extra payments or fees.
- The payment is principal and interest only: property tax, insurance, HOA dues and mortgage insurance are extra.
Worked examples
Each example is checked against the calculator on every build.
- Loan amount $300,000.00, Interest rate 6.5%, Loan term (years) 30 gives Monthly payment $1,896.20, Total interest $382,633.47, Payment over 15 years $2,613.32, Payment over 20 years $2,236.72.Source: Example 6.111: $99,596 at 5.35% for 30 years, $556.16 a month (rounded up). https://openstax.org/books/contemporary-mathematics/pages/6-12-renting-and-homeownership (retrieved 2026-10-18)
- Loan amount $300,000.00, Interest rate 7%, Loan term (years) 30 gives Monthly payment $1,995.91, Total interest $418,526.69.Source: Example 6.111: $99,596 at 5.35% for 30 years, $556.16 a month (rounded up). https://openstax.org/books/contemporary-mathematics/pages/6-12-renting-and-homeownership (retrieved 2026-10-18)
- Loan amount $99,596.00, Interest rate 5.35%, Loan term (years) 30 gives Monthly payment $556.16.Source: Example 6.111: $99,596 at 5.35% for 30 years, $556.16 a month (rounded up). https://openstax.org/books/contemporary-mathematics/pages/6-12-renting-and-homeownership (retrieved 2026-10-18)
- Loan amount $300,000.00, Interest rate 0%, Loan term (years) 30 gives Monthly payment $833.33, Total interest $0.00.
How it works
With loan L ($300,000 by default), yearly rate j (percent) and Y years (30 by default):
- Monthly rate r = j ÷ 1,200, and number of payments n = 12 × Y.
- Monthly payment M = L × r ÷ (1 − (1 + r)^−n), the same as OpenStax’s P × r(1 + r)^n ÷ ((1 + r)^n − 1). At 0%, M = L ÷ n.
- Total interest = M × n − L (0 at 0%). Total of payments = L + total interest.
- Payments over 15, 20 and 30 years = M with n = 180, 240 and 360, at the same rate.
Loan $1,000 to $1 billion; rate 0% to 30%; term 1 to 50 years. Payments are not rounded between steps; money shows to the cent, rounded half up (OpenStax rounds a payment up to the next cent; on its example both give $556.16).
Assumptions
- A fixed rate for the whole term, monthly payments, no extra payments, and no fees.
- The payment is principal and interest only.
Worked examples by hand
$300,000 at 6.5% for 30 years (the default). r = 0.065 ÷ 12; n = 360. M = $1,896.20; total interest = 1,896.204 × 360 − 300,000 = $382,633.47. Over 15 years M = $2,613.32; over 20 years $2,236.72.
$300,000 at 7% for 30 years. M = $1,995.91; interest $418,526.69.
$99,596 at 5.35% for 30 years (OpenStax Example 6.111). M = $556.16 (556.1577 before rounding).
$300,000 at 0% for 30 years. M = 300,000 ÷ 360 = $833.33; no interest.
Other questions people ask
What is the monthly payment on a $300,000 mortgage?
At 6.5% over 30 years, $1,896.20 a month in principal and interest. At 7% it is $1,995.91. Taxes and insurance come on top.
How much interest will I pay on a $300,000 mortgage?
At 6.5% over 30 years, $382,633.47: you pay $682,633.47 in all for the $300,000. Over 15 years at the same rate, the interest is $170,397.98.
What is the payment on $300,000 over 15 years?
At 6.5%, $2,613.32 a month: $717.12 more than over 30 years, but $212,235.49 less interest.
How much income do I need for a $300,000 mortgage?
It depends on your lender, your other debts and your taxes and insurance. The payment here is the principal and interest part; a lender adds the rest and compares the total with your income.
How is the payment calculated?
With loan L, monthly rate r = yearly rate ÷ 12 and n payments, the payment is L × r ÷ (1 − (1 + r)^−n). At 0%, it is L ÷ n: $300,000 ÷ 360 = $833.33.