Boat Loan Balloon Payment Calculator
This calculator estimates periodic payments and the final balloon payment for a boat loan. It supports either monthly or bi‑weekly schedules and two payment methods: amortizing payments that leave a balloon at maturity, or interest‑only payments followed by a balloon.
Use the fields to enter loan amount, annual interest rate, loan term, payment frequency (monthly or bi‑weekly), and the balloon as either a fixed amount or a percent of the original loan. Results are rounded for display; see accuracy notes.
Compute the periodic payment needed to amortize the loan amount minus the balloon over the scheduled payments, with a remaining balloon paid at maturity.
Inputs
Advanced inputs
Balloon amount (absolute)
Balloon amount (percent)
Results
Periodic payment
$450.97
Balloon payment (maturity)
$0.00
Total paid (payments + balloon)
$58,626.26
Total interest paid
$8,626.26
| Output | Value | Unit |
|---|---|---|
| Periodic payment | $450.97 | currency |
| Balloon payment (maturity) | $0.00 | currency |
| Total paid (payments + balloon) | $58,626.26 | currency |
| Total interest paid | $8,626.26 | currency |
Visualization
Methodology
For the amortizing-with-balloon method, the tool computes the periodic interest rate by dividing the annual nominal rate by the payments per year. It calculates the payment that amortizes the principal portion (loan minus balloon) across the scheduled payments using the standard annuity formula. The balloon remains as a final lump sum at maturity.
For the interest-only method, periodic payments equal interest on the full principal; the principal (or specified balloon) is paid at maturity. All computations assume constant nominal interest rate and fixed payment schedule.
Worked examples
Example 1: $50,000 loan, 6.5% annual, 5 years, bi‑weekly payments (26/year), 20% balloon: calculator shows the bi‑weekly payment to amortize $40,000 over 130 payments and a $10,000 balloon at maturity.
Example 2: $30,000 loan, 5.0% annual, 3 years, monthly payments, interest-only method, balloon equals full principal: monthly payments cover interest only and the $30,000 principal is due at maturity.
Further resources
External guidance
Expert Q&A
Does bi‑weekly frequency reduce the total interest compared with monthly?
Bi‑weekly frequency changes the number of compounding periods and payment timing. If payments are sized and scheduled to match nominal rate conventions, bi‑weekly can lead to a different amortization path; use the calculator to compare. This tool assumes nominal annual interest divided by payments-per-year.
What rounding and accuracy can I expect?
Displayed values are rounded to typical currency precision. Internal calculations use standard floating arithmetic; results may differ slightly from lender statements due to day-count conventions, compounding rules, fees, or rounding. See citations for standards and the accuracy caveat below.
Is this a loan offer or a statement of legal terms?
No. This calculator provides estimates only and is not an offer, disclosure, or legal advice. Consult your lender for exact payoff schedules, fees, and contract terms.
Can I model a balloon larger than the loan or zero?
The tool allows explicit balloon amounts or percentages. A balloon greater than the loan is mathematically allowed but unlikely in practice; check inputs. If 'No balloon' is selected, the loan amortizes fully over the term.
Sources & citations
- NIST — Numerical Methods and Software Reliability guidance — https://www.nist.gov
- ISO 9001 — Quality management systems (calculation and validation best practices) — https://www.iso.org/iso-9001-quality-management.html
- IEEE Standards Association — Software and numerical standards — https://standards.ieee.org
- OSHA — Accuracy and safety in workplace processes (governance reference) — https://www.osha.gov