How the Down Payment Shapes the Whole Loan
The down payment is the cash you put toward the home up front, and it shapes almost every other number in the mortgage. A larger down payment means a smaller loan, a smaller monthly payment, less total interest, and a lower loan-to-value ratio that may unlock a better interest rate. It also means a much bigger pile of cash leaving your bank account on the closing date. This calculator lets you slide the down payment up or down and see all the consequences instantly — what changes, what doesn't, and where the cliffs are.
The 20% Threshold
The most discussed down payment number is 20%. This isn't a hard requirement — most loan programs allow much less — but it is the threshold at which Private Mortgage Insurance (PMI) becomes optional rather than mandatory. PMI is a charge added to your monthly mortgage that protects the lender (not you) if you default. It typically runs 0.5 to 1.5 percent of the loan amount per year. On a $400,000 loan that's $2,000 to $6,000 annually — money you pay every month until your loan-to-value ratio drops below 80%, which can happen either by paying down the principal or by the home appreciating.
Other Loan Programs
Conventional loans typically allow 5 to 20 percent down. FHA loans (US) allow as low as 3.5 percent down with mortgage insurance for the life of the loan. VA loans (US, for military) allow zero down with no monthly mortgage insurance. USDA loans (US, rural) allow zero down. UK and Canadian markets have their own programs with similar low-down-payment options. The trade-off is always the same: less cash up front means more cash over time in the form of insurance premiums and higher interest.
Loan-to-Value Ratio
The loan-to-value ratio (LTV) is the loan divided by the home value. Putting 20% down gives you 80% LTV. Putting 10% down gives you 90% LTV. Lenders care a lot about LTV because it measures how much skin in the game the borrower has. The LTV thresholds at 80%, 90%, and 95% each tend to come with different interest rate offers. A small additional down payment that pushes you across one of these thresholds can save more in interest over the life of the loan than the down payment itself, so it's worth checking what rate tier your prospective LTV falls into.
Should You Put Down More?
The temptation to put down as much as possible to minimize the loan size has to be weighed against keeping cash on hand for emergencies, repairs, and opportunities. A common rule of thumb is to keep at least three to six months of expenses in liquid savings after the down payment closes. Another consideration is the opportunity cost: cash invested in the down payment isn't earning returns elsewhere. If your mortgage rate is 7% and your alternative investment expectation is 5%, paying down the mortgage faster wins. If the math goes the other way, investing wins. Most homebuyers don't optimize this perfectly and that is fine — both choices are reasonable.
Closing Costs
The down payment is not the only cash needed at closing. Closing costs typically run 2 to 5 percent of the home price and cover lender fees, title insurance, escrow setup, taxes, and inspections. On a $400,000 home, that's another $8,000 to $20,000 on top of the down payment. Some loan programs allow rolling closing costs into the loan; others let you negotiate seller concessions. Either way, when budgeting for a purchase, plan for the down payment plus 3 percent of the home price as a baseline cash requirement.
Saving for a Down Payment
The two biggest accelerators of down payment savings are reducing the price target and increasing the saving rate. Looking at homes 10 percent below your max budget reduces the down payment goal by 10 percent. Pushing your monthly savings rate from 10 to 15 percent of income compounds quickly. A high-yield savings account or money market is the standard parking place for medium-term down payment savings, since the timeline is too short for stocks but long enough that earning 4-5% beats checking. Many countries also have tax-advantaged accounts specifically for first-time homebuyers (US: First-Time Homebuyer IRA exception; Canada: FHSA; UK: Lifetime ISA).
Frequently Asked Questions
Does the calculator include taxes and insurance?
The monthly payment shown is principal and interest only. Property taxes, homeowner's insurance, HOA fees, and PMI are typically added on top. Estimate property tax at around 1 to 2 percent of home value annually (varies widely by location), and homeowner's insurance at $1,000 to $2,500 per year for typical homes.
Can I change the down payment after applying?
Generally yes, before closing. Your loan estimate will update with the new numbers, and the lender will reissue documents. If you increase your down payment significantly you may also qualify for a better interest rate.
What about gift money from family?
Most loan programs allow some or all of the down payment to come from a gift, with documentation. The lender will require a gift letter from the donor and may want to see the funds in your account for a specified period (often 60 days) before closing.
This calculator is free and runs entirely in your browser. Use it as a planning tool — actual mortgage offers depend on your credit, debt-to-income ratio, and the lender's specific programs.
Try also: Mortgage Calculator · Savings Interest Calculator