How to Calculate Your First Home Budget

Buying your first home is exciting, but before you start browsing through listings or scheduling tours, you need a clear budget.

Whether you have a at home in Phoenix or a apartment in baltimoreKnowing how to calculate your first home budget can help you shop with confidence, avoid financial pressure, and make stronger offers. From upfront costs to monthly expenses and long-term planning, this Redfin guide will teach you how to determine what you can realistically afford.

Why calculating your housing budget is important

Your housing budget determines more than just your price range. It affects:

• The houses you should focus on
• How much cash you need up front
• Whether your monthly payment will feel manageable
• How competitive your offer can be

Without a clear budget, buyers often experience financing surprises, delayed closings or buyer fatigue as they tour homes outside their comfort zone.

Step 1: Calculate your gross monthly income

Start with your gross monthly income, which is your income before taxes and deductions.

Involve:

• Salary or hourly wage
• Bonuses or commissions
• Additional income
• Rental or investment income

If your income fluctuates, calculate an average over the past one to two years.

Step 2: Understand your debt-to-income ratio

Lenders use your debt to income ratioor DTI, to determine how much you can borrow.

There are two types:

Front end DTI – This only includes your future housing costs.

Backend DTI – This includes housing costs plus other debts such as student loans, car payments, and credit cards.

Most lenders prefer:

• Front-end DTI below 28%
• Backend DTI under 36 – 43%

For example, if your gross monthly income is $6,000, your total monthly debt, including your future mortgage payment, generally should not exceed $2,160 to $2,580, depending on the loan program. Some loan programs allow higher DTIs depending on credit score and other factors.

Step 3: Follow the 28/36 rule as a starting point

A commonly used budget guideline is the 28/36 rule.

• Spend no more than 28% of gross income on housing
• Do not spend more than 36% of gross income on total debts

If you earn $5,500 per month, 28% equals $1,540. That would be your maximum recommended home payment, including principal, interest, property taxeshomeowners insurance and HOA fees, if applicable.

Please note that this is a guideline and not a requirement. Your comfort level is more important than achieving a specific percentage.

Step 4: Estimate your total monthly rent payment

Your mortgage payment includes more than just principal and interest. Budget for the full monthly housing costs, also called PITI:

• First name
• Interest
• Property taxes
• Homeowners Insurance

You may also need to include the following:

• Private mortgage insurance if your down payment is less than 20 percent
• HOA dues
• Flood insurance in certain areas

This entire number determines affordability, not just the loan amount.

Step 5: Calculate your initial costs

Your first home budget should take into account the upfront costs, not just them monthly payments.

Deposit

Many starters on the market put down between 3% – 10%, depending on the loan type. Some loan programs require as little as 3% down, while others such as VA Loans cannot require a deposit.

Closing costs

Closing costs typically range from 2% – 5% of the purchase price and may include:

• Loan Origination Fees
• Valuation
• Title insurance
• Escrow costs
• Prepaid taxes and insurance

For a $350,000 home, closing costs can range from $7,000 to $17,500.

Moving and setup costs

Don’t forget:

• Moving costs
• Utility deposits
• First repairs
• Furniture or appliances

These costs add up quickly and should be part of your overall savings goal.

Step 6: Check your monthly budget honestly

Evaluate your current expenses before committing to a home price.

Ask yourself:

• How much do I save monthly?
• Can I still build an emergency fund?
• Am I planning big changes in my life, like starting a business or changing jobs?

Just because a lender approves you for a certain amount doesn’t mean you have to spend that much.

Zach Buchenau from Be the budget says he encourages first-time buyers “to use the lender’s approval number as a luxury starting point and then build their budget from scratch based on their real lives.

‘Your lender does not know your life goals – Have a baby, take an annual vacation, retire at 50 – but those things determine your real financial life. If you buy less than you qualify for and give yourself some margin, you can always move up in a few years if you need to. Getting yourself out of a mortgage that is stifling your lifestyle is a much more difficult problem to solve both financially and emotionally.”

Step 7: Leave room for the costs of homeownership

According to Zach, the often overlooked costs are small, recurring expenses that pile up: lawn care, city or homeowners’ association fees, minor repairs, or a washing machine that floods your laundry room after six months. “I tell people to budget 1% to 2% of the home’s value per year, depending on the age of the home, just for maintenance,” says Zach. “If that number, plus your mortgage, taxes and insurance, makes you uncomfortable, that’s your sign that the house is too expensive.”

Budget for:

• Maintenance and repairs
• Landscaping
• Pest control
• Replacement of the device
• Higher energy bills

A common rule of thumb is to set aside 1% of the home value annually for maintenance. For a $400,000 home, that’s about $4,000 per year.

Step 8: Get pre-approved to confirm your coverage

Once you’ve calculated your personal comfort zone, speak with a lender and be approved in advance. A prior approval:

• Confirms the amount you qualify for
• Displays an estimated interest rate
• Strengthens your offer if you find a home

This step converts your estimated budget into a realistic purchasing range.

Example: Calculation of a first housing budget

Let’s say you earn $6,000 per month before taxes and have $400 in monthly debt.

Using the 36% rule:

• 36 percent of $6,000 equals $2,160
• Subtract $400 in debt
• That leaves $1,760 for housing

If current rates bring your estimated mortgage payment to $1,750 per month, including taxes and insurance, that may be within your target range.

You then calculate how much house price corresponds to that payment based on the interest rates and your down payment.