You buy out a sibling by taking a new mortgage in your name that pays off the old loan and puts cash in your sibling's hands for their share of the equity. In practice it is a cash-out refinance with a very specific use of the cash. The catch is the payment. If your old loan was cheap, the new one can cost far more. Here is the math for Scottsdale, Phoenix, and the rest of Metro Phoenix, and what else you can try.

The buyout math, step by step

Start with the value. An appraisal sets it so neither side argues about a Zillow guess. Subtract the mortgage balance to get the equity, then multiply by your sibling's share. Add the closing costs, and that is your new loan. Here is a real scale.

At about 72% of the value, that loan sits under the 80% cap that conventional lenders commonly use on a cash-out refinance of a primary home. If the share you owe is bigger, or the value comes in lower, you can run into that cap fast. Our guide to the appraisal on an Arizona refinance shows how value moves the numbers.

The loan is rarely the hard part. The hard part is the jump from a payment you have had for years to a payment priced at today's rate.

What the new payment looks like

This is where people get surprised. Suppose your $250,000 balance is at 3.5%, which is a payment of about $1,123 in principal and interest. A $434,000 loan at 7.25% costs about $2,961. That is $1,838 more every month. You are borrowing more, and you are borrowing it at a higher rate than the money you are replacing. Freddie Mac put the average 30 year rate at 7.18% this week, and a cash-out loan usually prices a bit higher. The 7.25% here is an illustration, not a quote. For where rates are heading, see our Arizona refinance rates hub.

If the old payment is a lot cheaper than what you can get now, a full refinance may not be the best move. Compare the options below.

The second loan option looks cheaper, and in this example it is, by about $526 a month. But the 9% is a placeholder for a variable rate, and an interest only payment does not pay down anything. Our guide to cash out refinance vs HELOC in Arizona goes through when each one wins, and the cash out refinance guide for Arizona covers the basics of the loan itself.

Use the calculator below to test the new loan. It shows principal and interest only, and the numbers are estimates.

Run your own numbers

How the paperwork and title work

At closing your sibling signs a deed that gives up their interest, and the title company records it. You and your sibling should agree in writing on the value, the payoff amount, and the date before the loan is submitted. If you are married, ask your loan officer whether your spouse needs to sign anything, since Arizona is a community property state and lenders often ask for a spouse's signature on certain documents even when the spouse is not on the loan.

Some programs treat a buyout tied to an inheritance, divorce, or separation as a limited cash-out refinance, which prices better than a standard cash-out loan. Whether a sibling buyout qualifies depends on how your sibling came onto the title, the investor's rules, and the documents you can provide. Ask before you assume. If the house came to you both from a parent, our guide on refinancing an inherited house in Arizona covers the most common version of this.

Taxes and what happens if a sibling says no

If you pay full market value, the transaction is generally a sale, and your sibling may owe tax on any gain. If you pay less than the house is worth, the difference may count as a gift. The IRS explains the rules on its gift tax page. A gift of equity can also help a family transaction work, and we cover the lending side in our guide to a gift of equity in Arizona. Bring a CPA in early.

If your sibling will not engage, co-owners cannot be forced to sell to each other, but either one can ask a court to order a partition, which can end in a forced sale. You can read Arizona's laws at azleg.gov. A written offer based on an appraisal is usually faster and leaves more money on the table for both of you than a court fight. Keep it civil and keep it in writing.

Before you start

Pull your current mortgage statement, a recent tax bill, your homeowners policy, and any document that shows how the two of you hold title. If the house is in a trust, add the trust paperwork. The Consumer Financial Protection Bureau has plain language guides to the loan estimate you will receive.

Expect the process to take 30 to 45 days. The appraisal usually lands in the first two weeks, and the slowest step is often not the lender at all. It is getting two people to agree on a number and a signing date. Settle the value and the payoff in writing first, tell the title company who is signing, and keep your sibling in the loop at each step. Many buyouts fall apart over a surprise, not over the money, and a sibling who feels informed is far more likely to sign on the day you need them to. If you live in Scottsdale and your sibling lives out of state, ask the title company about a mobile notary or remote signing so the closing does not slip a week.

You can see the products we shop on our loan programs page, learn who we are on the about us page, and walk through the steps on our process page. You can also start at pillarmortgagegroup.com. If you keep the house and decide to trade up later, Arizona Luxury Property Search is where to browse Scottsdale and Valley listings.

Frequently asked questions