Should You Add Your Grown-Up Kids to Your Buy-To-Let Mortgage?

A reader asked The Guardian’s financial expert about the risks and rewards of transferring property to their children.

The Big Question

“My wife and I own a rental property, which once was our family home. We’re thinking of adding our adult children, aged 26 and 31, to the mortgage. Can we? If not, what’s the best way to hand over the property without hefty fees?”

To Add or Not to Add?

Good news! Yes, you can add your children to your buy-to-let mortgage. But, before you make that move, here’s what you need to know:

  1. Debt Responsibility: By adding them to the mortgage, they’d be on the hook for the mortgage debt, just like you. If something happened and you couldn’t keep up with payments, they’d need to cover it.
  2. Affecting Their Future Home Dreams: If your kids haven’t bought their own place yet, this move could make things trickier for them later on. It might mess up their chances of securing their own mortgage down the line. Plus, they would lose out on a great benefit meant for first-time home buyers.

First-Time Buyer Perks

For first-time property buyers in the UK, there’s a relief from stamp duty land tax (SDLT). It means they wouldn’t have to pay this tax on the first £425,000 of a property that’s priced up to £625,000. Anything above £425,000 and below £625,000 attracts a 5% SDLT. By joining your mortgage, your children would give up this perk.

Already Homeowners? Here’s the Catch!

If your kids already own their homes, there’s another twist. Being added to your buy-to-let mortgage might count as them getting a second property. And when that happens, they’d be hit with a higher SDLT rate. This isn’t just the standard rate; it’s the standard rate plus an additional three percent. This is based on the amount they’d be responsible for on your mortgage.

The Simplest Solution

If the end goal is to ensure the home remains in the family after you’re gone, why not leave it to them in your will? This way, you don’t complicate their financial matters now. And here’s another thought: maybe sit down with them and chat. You might find that they’d be happier if you sold the house and divided the cash between them. By doing this, if you live for another seven years after gifting them the proceeds, it could help them save on inheritance tax.


Adding your children to your buy-to-let mortgage has its pros and cons. It’s essential to weigh these up, consider their future financial health, and maybe even have a family chat about what everyone wants. Whatever you decide, make sure it’s in everyone’s best interest.