Purchasing real estate with a mortgage is often the most extensive personal investment most people make. How much you can afford to borrow depends on several factors, not just what a bank is willing to lend you. You need to evaluate not only your finances but also your preferences and priorities.

Here is everything you need to consider to determine how much you can afford.

How Much Mortgage Can I Afford?

Generally speaking, most prospective homeowners can afford to finance a property whose mortgage is between two and two-and-a-half times their annual gross income. Under this formula, a person earning $100,000 per year can only afford a mortgage of $200,000 to $250,000. However, this calculation is only a general guideline.”

Ultimately, when deciding on a property, you need to consider several additional factors. First, it’s a good idea to have some understanding of what your lender thinks you can afford (and how it arrived at that estimation). Second, you need to have some personal introspection and figure out what type of home you are willing to live in if you plan on living in the house for a long time and what other types of consumption you are ready to forgo—or not—to live in your home.

How Do Lenders Determine Mortgage Loan Amounts?

While each mortgage lender maintains its own criteria for affordability, your ability to purchase a home (and the size and terms of the loan you will be offered) will always depend mainly on the following factors.

Gross Income 

This is the level of income a prospective homebuyer makes before taking out taxes and other obligations. This is generally deemed your base salary plus any bonus income and can include part-time earnings, self-employment earnings, Social Security benefits, disability, alimony, and child support.

Front-End Ratio

Gross income plays a vital part in determining the front-end ratio, also known as the mortgage-to-income ratio. This ratio is the percentage of your yearly gross income that can be dedicated toward paying your mortgage each month. The total amount of money that makes up your monthly mortgage payment consists of four components, known as PITI: principal, interest, taxes, and insurance (both property insurance and private mortgage insurance, if required by your mortgage).

A good rule of thumb is that the front-end ratio based on PITI should not exceed 28% of your gross income. However, many lenders let borrowers exceed 30%, and some even let borrowers exceed 40%.

Back-End Ratio

Also known as the debt-to-income ratio (DTI), it calculates the percentage of your gross income required to cover your debts. Debts include credit card payments, child support, and other outstanding loans (auto, student, etc.).

In other words, if you pay $2,000 each month in debt services and you make $4,000 each month, your ratio is 50%—half of your monthly income is used to pay the debt.

However, a 50% debt-to-income ratio isn’t going to get you that dream home. Most lenders recommend that your DTI not exceed 43% of your gross income. To calculate your maximum monthly debt based on this ratio, multiply your gross income by 0.43 and divide by 12.

Your Credit Score

If one side of the affordability coin is income, then the other side is your debt.

Mortgage lenders have developed a formula to determine the level of risk of a prospective homebuyer. The formula varies but is generally determined by using the applicant’s credit score. Applicants with a low credit score can expect to pay a higher interest rate, also referred to as an annual percentage rate (APR), on their loan. If you want to buy a home soon, pay attention to your credit reports. Be sure to keep a close eye on your reports. If there are inaccurate entries, it will take time to get them removed, and you don’t want to miss out on that dream home because of something that is not your fault.

How to Calculate a Down Payment

The down payment is the amount that the buyer can afford to pay out-of-pocket for the residence, using cash or liquid assets. Lenders typically demand a down payment of at least 20% of a home’s purchase price, but many let buyers purchase a home with significantly smaller percentages. Obviously, the more you can put down, the less financing you’ll need, and the better you look to the bank.

For example, if a prospective homebuyer can afford to pay 10% on a $100,000 home, the down payment is $10,000, which means the homeowner must finance $90,000.

Besides the amount of financing, lenders also want to know the number of years for which the mortgage loan is needed. A short-term mortgage has higher monthly payments but is likely less expensive over the duration of the loan.

How Lenders Decide

Many different factors go into the mortgage lender’s decision on homebuyer affordability, but they boil down to income, debt, assets, and liabilities. A lender wants to know how much income an applicant makes, how many demands there are on that income, and the potential for both in the future—in short, anything that could jeopardize its ability to get paid back. Income, down payment, and monthly expenses are generally base qualifiers for financing, while credit history and score determine the rate of interest on the financing itself.

Personal Considerations for Homebuyers

A lender could tell you that you can afford a considerable estate, but can you? Remember, the lender’s criteria look primarily at your gross pay and other debts. The problem with using gross income is simple: You are factoring in as much as 30% of your paycheck—but what about taxes, FICA deductions, and health insurance premiums, In addition, consider your pre-tax retirement contributions and college savings, if you have children. Even if you get a refund on your tax return, that doesn’t help you now—and how much will you get back?

That’s why some financial experts feel it’s more realistic to think in terms of your net income (aka take-home pay) and that you shouldn’t use any more than 25% of your net income on your mortgage payment. Otherwise, while you might be able to pay the mortgage monthly, you could end up “house poor.” 

The costs of paying for and maintaining your home could take up such a large percentage of your income—far and above the nominal front-end ratio—that you won’t have enough money left to cover other discretionary expenses or outstanding debts or to save for retirement or even a rainy day. Whether or not to be house poor is mostly a matter of personal choice; getting approved for a mortgage doesn’t mean you can afford the payments.

Pre-Mortgage Considerations

In addition to the lender’s criteria, consider the following issues when contemplating your ability to pay a mortgage:

1. Income

Are you relying on two incomes to pay the bills? Is your job stable? Can you easily find another position that pays the same, or better, wages if you lose your current job? If meeting your monthly budget depends on every dime you earn, even a small reduction can be a disaster.

2. Expenses

The calculation of your back-end ratio will include most of your current debt expenses, but you should consider future costs like college for your kids (if you have them) or your hobbies when you retire.

3. Lifestyle

Are you willing to change your lifestyle to get the house you want? If fewer trips to the mall and a little tightening of the budget don’t bother you, applying a higher back-end ratio might work out fine. If you can’t make any adjustments or already have multiple credit card account balances—you might want to play it safe and take a more conservative approach in your house hunting.

4. Personality

No two people have the same personality, regardless of their income. Some people can sleep soundly at night knowing that they owe $5,000 per month for the next 30 years, while others fret over a payment half that size. The prospect of refinancing the house to afford payments on a new car would drive some people crazy while not worrying others at all.

Costs Beyond the Mortgage

While the mortgage is undoubtedly the most considerable financial responsibility of homeownership, there are many additional expenses, some of which don’t go away even after the mortgage is paid off. Smart shoppers would do well to keep the following items in mind:

1. Property Taxes

If you own a home, expect to pay property taxes, and understanding how much you will owe is an important part of a homebuyer’s budget. The city, township, or county establishes your property tax based on your home and lot size and other criteria, including local real estate conditions and the market.

According to the Tax Foundation, the effective average rate nationwide for property taxes is 1.1% of the home’s assessed value. This amount varies by state, and some states boast lower property taxes than others. For example, New York’s is an average of 1.4%, but Oklahoma’s is 0.88%. You will always have to account for paying property tax, even when your mortgage is paid off in full.

2. Home Insurance

Every homeowner needs home insurance to protect their property and possessions against natural and human-made disasters, like tornados or theft. If you are purchasing a home, you will need to price out the appropriate insurance for your situation. Most mortgage companies won’t let you purchase a home without home insurance that covers the purchase price of their home. In fact, you may need to show proof of home insurance to be approved by your mortgage lender.

In 2018, the most recent statistics available as of early 2021, the average premium for the most common type of home insurance in the U.S. was approximately $1,200. But the amount goes up depending on the type of insurance you need and the state you reside in.

3. Maintenance

Even if you build a new home, it won’t stay new forever, nor will those expensive significant appliances, such as stoves, dishwashers, and refrigerators. The same applies to the home’s roof, furnace, driveway, carpet, and even the paint on the walls. If you are house poor when you take on that first mortgage payment, you could find yourself in a difficult situation if your finances haven’t improved by the time your home requires significant repairs.

4. Utilities

Heat, insurance, electricity, water, sewage, trash removal, cable television, and telephone services cost money. These expenses are not included in the front-end ratio, nor are they calculated in the back-end ratio. Nevertheless, they are unavoidable for most homeowners.

In addition, consider that a bigger house means higher utility bills due to heating and cooling energy needs to condition the bigger space. Many people overlook that when they see a big charming home.

5. Association Fees

Many condominiums and coops and specific gated neighborhoods or planned communities assess monthly or yearly association fees. Sometimes these fees are less than $100 per year; other times, they are several hundred dollars per month. Some communities include lawn maintenance, snow removal, a community pool, and other services.

Some fees are only used for the administration costs of running the community. It’s important to remember that while an increasing number of lenders include association fees in the front-end ratio, these fees are likely to increase over time.

6. Furniture and Decor

Before you buy a new house, take a good look at the number of rooms that will need to be furnished and the number of windows that will require covering.

The Bottom Line

The cost of a home is the single largest personal expense most people will ever face. Before taking on such an enormous debt, take the time to do the math. After you run the numbers, consider your situation and think about your lifestyle—not just now but into the next decade or two. Before you purchase your new home, consider not only what it costs you to buy it but how your future mortgage payments will impact your life and budget. Then, get loan estimates for the type of home you hope to buy from several different lenders to get real-world information on the kinds of deals you can get.