Washington HELOC Calculator

By SoFi Editors | Updated January 29, 2026

> A Washington HELOC calculator is a useful tool for homeowners who are sitting on comfortable levels of home equity. If you have a good credit score and otherwise meet lender qualifications, you might be able to borrow up to 90% of your equity using a home equity line of credit (HELOC). But is that a good fit for your budget? This guide will show you what your monthly payments might be on a HELOC at key points in your borrowing journey. Along the way, we’ll make sure you understand exactly what a home equity line of credit is and how it works.


  • Key Points
  • •  A home equity line of credit is a revolving credit agreement that allows for multiple withdrawals and repayments up to a specific credit limit.
  • •  Borrowing capacity is determined by your home’s current market value minus any existing mortgage balances.
  • •  A HELOC payment calculator computes estimated payment amounts during the two phases of a HELOC.
  • •  The initial phase is the draw period, typically lasting 10 years, while the second phase, the repayment period, often spans 20 years.
  • •  Interest paid on a HELOC may be tax-deductible for homeowners who itemize.



Calculator Definitions

•   HELOC Balance: If you don’t yet have a HELOC, the balance for the purpose of the calculator is the amount you think you would like to borrow. If you already have a HELOC, your current balance is listed on your account statement.

•   Current Interest Rate: You’ll be charged a percentage of the borrowed amount as interest. Your interest rate can change periodically as most HELOCs have variable interest rates. If you’re in the market for a HELOC, lenders can quote an initial rate.

•   Draw Period: This is the initial window, usually five to 10 years, during which borrowers using a HELOC can withdraw funds as needed, up to the credit limit. At this stage, you’ll likely have the ability to make interest-only payments, though you could also make payments toward the principal.

•   Repayment Period: Repayment follows the draw phase. Further withdrawals are prohibited and borrowers begin making payments that include a portion of the principal as well as interest. This phase typically lasts 10 or 20 years. Longer repayment periods usually equal lower monthly payments but more interest paid in total.

•   Monthly Interest Payment: This is the minimum cost required to carry your balance during the draw phase of the HELOC. It does not reduce the principal amount owed unless you choose to pay more than the minimum.

•   Monthly Principal and Interest Payment: This is the total required monthly obligation once the second phase of the credit line begins. This amount is calculated to ensure the total balance is satisfied by the end of the term.

How to Use the Washington HELOC Calculator

Accurate data entry is required to generate meaningful projections. Follow this guide as you use the calculator for the first time.

Step 1: Enter Your Planned or Actual HELOC Balance

Type in the amount of the credit line you have used (or the amount you plan to use). Bear in mind that your credit limit with a HELOC may be much higher. But you only pay interest on what you actually borrow.

Step 2: Estimate Your Interest Rate

Enter your current HELOC interest rate or the rate you’re being quoted by a prospective lender. Because most HELOCs feature a variable rate, it is helpful to use the calculator to test payment amounts with the current rate as well as a slightly higher rate.

Step 3: Choose the Length of the Draw Period

Select the number of years you would like to access funds, up to 10 years.

Step 4: Select Your Repayment Period

Enter the length of the second phase, commonly 10 or 20 years, to calculate your monthly payments once the principal is included. Remember, a longer term here will lower your monthly payment estimate but could cost you more in interest over the long haul.

Step 5: Review Your Results

Analyze the projected payments for both phases to ensure they remain within your financial reach. Learn more about how to use the calculator data below.

What Is a Home Equity Line of Credit?

If using the free HELOC calculator has you thinking a HELOC might be a good fit for your lifestyle and budget, take the time to learn more about this unique way of borrowing money. Here are the basics: A HELOC is technically a second mortgage, assuming you’re still paying off your original home loan. Your home is the collateral for the funds you borrow, and if you don’t repay what you owe, a lender could foreclose.

As noted above, HELOCs have two phases: a draw period, often 10 years, followed by a repayment period that lasts up to 20 years. Because these products typically feature variable interest rates, the cost of borrowing can shift with market conditions. A HELOC agreement will specify how often the interest rate can change and by how much, so that the rate shifts shouldn’t be a complete surprise.

During the draw period, many lenders won’t require you to repay any of the principal — you’ll only pay interest on the amount you have borrowed. A HELOC interest-only calculator can estimate these payments. The fact that you can borrow in increments, as the money is needed, and only pay interest makes HELOCs an attractive solution for homeowners who need money for ongoing projects, such as a series of renovations.

A HELOC repayment calculator will come in handy when you hit the second phase of the HELOC: repayment. It’s important to be prepared for this switch, as your monthly payment amount can grow substantially when the principal is added in. The repayment phase could last up to 20 years.

Recommended: Different Types of Home Equity Loans

The average home equity for an owner in Washington is close to $300,000. Homeowners in the state have experienced a significant increase in borrowing power over the last five years due to historic property appreciation. Average home equity levels increased 70% between 2020 and 2025. In Seattle, the median home sale price in 2020 was $755,000. By late 2025, it had reached $865,000. This rise in home value and equity is part of a larger national trend, as you can see in the graphic — no surprise that owners across the nation are increasingly exploring how to get equity out of their home.

How to Use the HELOC Calculator Data to Your Advantage

You’ve already seen how monthly payment estimates from the free HELOC calculator can be generated and then compared against your budget. But there are additional ways to use this data:

Assess the impact of variable interest rates: You can never truly know what the future holds for interest rates, but it’s a good idea to use the calculator to test what-if scenarios by manually adjusting the “current interest rate” cost upward by one or even two percentage points. This will allow you to see if your budget has enough flexibility to handle upward rate moves.

See the impact of principal payments: Another smart way to use the HELOC payment calculator is to see how making interest-only payments vs. paying down the principal during the draw period might affect costs when you reach the repayment stage. Run the calculator with your anticipated current HELOC balance and note the cost of the “principal and interest” repayment. Then reduce the HELOC balance by, say, 20% and run the numbers again. You’ll see how much the principal and interest payment would be cut if you were to pay back one-fifth of what you owe during the draw phase. This might not be possible for every homeowner, but it may be motivating.

Decide on using a HELOC for debt consolidation: Add up your total monthly debt on your credit cards and type that total into the “HELOC balance” field. The calculator will give you an estimate of what monthly payments would be now and in the future were you to pay off the cards using a HELOC. If you see the potential for savings, a HELOC might be the right move. Bonus: Instead of making multiple payments to different credit accounts, you would have one monthly HELOC payment.

Recommended: HELOC vs. Home Equity Loan

Tips on HELOCs

It’s probably already clear that you need to keep a close eye on interest rates and make your payments on time when you have a HELOC. These are some other ways to be smart about using this form of lending:

•  Shop around: Compare options from multiple lenders to find your best offer. Look for a competitive interest rate and low fees, as well as a repayment term and monthly payments that fit your budget. Use the HELOC payment calculator to run the numbers on each option.

•  Make a repayment plan: Before you draw funds, have a clear idea of how you will repay what you have borrowed. If the monthly principal and interest payment is a squeeze in your current household budget, do you foresee that your income will be higher when the draw phase ends? If not, dial back your spending plan.

•  Understand fees: Some HELOCs have closing costs or annual maintenance fees. Lenders may also have inactivity fees that are triggered if you don’t use the line of credit. And there could be early termination penalties if you close the account within a few years of opening it.

Alternatives to HELOCs

It’s a best practice to weigh all your financing options to ensure you choose the one that best aligns with your goals. So spend a little time learning other ways you might borrow money. Start by understanding what a home equity loan is, as it is often confused with a HELOC.

Home Equity Loan

A home equity loan, like a HELOC, uses your home as collateral. But money from a home equity loan comes as a lump sum and the loan has a fixed interest rate. The loan is repaid in equal monthly installments over a set period, anywhere from 5 to 30 years. It offers more predictability than a variable-rate HELOC but lacks the flexibility to re-borrow funds as you pay down your balance. And the principal-plus-interest payments begin as soon as you receive the funds. A home equity loan calculator can give you a sense of what payments could be based on your borrowed amount.

Home Improvement Loan

This is generally an unsecured installment loan. Since you won’t be using your home as collateral, it may carry a higher interest rate and have a lower borrowing limit than credit lines secured by equity. The money you borrow will come as a lump sum and is specifically intended for property upgrades. Loan repayment will begin at once and will be a consistent amount throughout the term.

Personal Line of Credit

Like a HELOC, this credit line offers revolving access to funds. However, it is typically unsecured and approval is based on your personal creditworthiness. It may have higher costs and more restrictive borrowing limits than a HELOC.

Cash-Out Refinance

This type of mortgage refinance replaces your existing primary mortgage with an entirely new, larger mortgage. You receive the difference between the old and new loan amounts in cash, which can be useful for large expenses. If you opt for this borrowing method, you’ll begin making your new (probably larger) mortgage payment immediately.

As you consider a cash-out refinance vs. a home equity line of credit, think about this: A refi likely only makes sense if you can secure a lower interest rate on your new loan than you had on your original mortgage. Don’t forget to factor closing costs in when you compute the costs.

The Takeaway

A HELOC calculator is a vital asset for any homeowner considering a revolving credit line. By providing detailed projections for both the draw and repayment stages, the tool allows you to avoid budget surprises when interest-only periods end. Your next step if you’re looking for a HELOC to fund major renovations or consolidate debt — or for any purpose — will be to get rate quotes from lenders so you can find the best fit for your situation.

SoFi now partners with Spring EQ to offer flexible HELOCs. Our HELOC options allow you to access up to 90% of your home’s value, or $500,000, at competitively lower rates. And the application process is quick and convenient.



Unlock your home’s value with a home equity line of credit from SoFi, brokered through Spring EQ.


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FAQ

What is the difference between a HELOC and a home equity loan?

A HELOC is a revolving credit line, so you can borrow and repay as needed, as long as the draw phase lasts. You won’t have to repay the principal until five to 10 years after you start borrowing. Throughout the life of the HELOC, your variable interest rate may fluctuate. A home equity loan is a lump-sum disbursement with a fixed interest rate and consistent monthly payments that start immediately. Both use your home as collateral.

How much can I borrow with a HELOC?

Lenders typically allow you to borrow up to 90% of your home equity with a HELOC, although lenders also tend to have a ceiling — a maximum amount they will loan to a borrower, regardless of how much equity they are sitting on.

Is a HELOC interest rate fixed or variable?

HELOCs usually have a variable interest rate. This means the monthly cost of borrowing can go up (or down) as rates change. The HELOC agreement you sign with the lender will make it clear in writing how often rates can change and by how much, so rate changes shouldn’t ever be a surprise.

Is the interest on a HELOC tax-deductible?

The interest you pay when borrowing money with a HELOC is deductible in the 2026 tax year. You’ll need to itemize on your return so that you can claim this deduction. Consult a qualified tax professional to confirm eligibility and also to track tax rules as they change in future years.

Learn more about home equity line of credits: