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    Loans / Marine

    Boat Loan Calculator

    Payment, total interest and the deposit effect for a boat loan. Marine loans often run longer than car loans, which lowers the payment and raises the interest.

    Monthly payment$843.10Amount financed$68,000Total interest$33,172
    Monthly payment
    $843.10
    120 months
    Amount financed
    $68,000
    After the deposit
    Total interest
    $33,172
    Over the term
    Total paid
    $101,172
    Including the deposit
    Term comparison
    Fixed rate, monthly payments; the deposit reduces the amount financed.
    Term comparison
    TermPaymentTotal interest
    60 mo$1,395$15,707
    120 mo$843.10$33,172
    180 mo$669.62$52,532
    240 mo$590.12$73,629
    Inspect the model
    Choose a quick result view, a scaled comparison, or the complete diagnostic set.
    Payment against term
    Stretching the term lowers the payment and raises the interest.
    Payment against term0.000312.51625.01937.521250.031562.5360 mo60 mo84 mo84 mo120 mo120 mo180 mo180 mo240 mo240 moBoat Loan Calculator
    Canonical equations
    The exact relationships implemented by this engine.

    M = P·i/(1 − (1+i)^−n) · Level payment amortisation.

    M·n − P · Total cost of borrowing.

    finance methodology

    A clear path from inputs to results.

    Payment, total interest and the deposit effect for a boat loan. Marine loans often run longer than car loans, which lowers the payment and raises the interest.

    Step-by-step methodWorked exampleAssumptions explained

    How to use

    1. Set boat price ($).
    2. Set deposit ($).
    3. Set annual rate (%).
    4. Set term (months).
    5. Read the headline metrics, then check the table for the detail.

    The formula

    M=P⋅i/(1−(1+i)−n)M = P·i/(1 − (1+i)^−n)

    Reference: Level payment amortisation at a fixed rate (Broverman, Mathematics of Investment and Credit).

    Worked example

    At the default inputs

    Inputs
    • Boat price ($): 85000; Deposit ($): 17000; Annual rate (%): 8.5; Term (months): 120
    Calculation path
    1. 1

      Monthly payment: $843.10 · Amount financed: $68,000 · Total interest: $33,172 · Total paid: $101,172

    Result

    Monthly payment: $843.10 · Amount financed: $68,000 · Total interest: $33,172

    Interpreting the result

    A $85,000 boat with a $17,000 deposit at 8.50% over 120 months is $843.10 a month.

    Assumptions & limitations

    • Fixed rate for the whole term.
    • No insurance, mooring or survey costs.

    Frequently asked questions

    Why do marine loans run longer?

    Boats depreciate more slowly than cars, so lenders accept longer terms — which raises the total interest.

    Does the deposit change the rate?

    Often yes; a larger deposit lowers the lender’s risk and can improve the quoted rate.

    Methodology last reviewed 2026-10-22. Results are informational and not financial or engineering advice — see our disclaimer.