How Much Down Payment Do You Need for an Assumable Mortgage in Colorado? 2026 Guide

One of the first questions buyers ask when they learn about assumable mortgages is: what do I have to put down?

It's a reasonable question, but it's asking about the wrong thing. Assumable mortgages don't work like traditional purchases. There is no "down payment percentage" to calculate. What you're covering instead is called the equity gap, and it's a fixed dollar amount, not a percentage of the home price.

Here's how it works.

The Equity Gap Explained

When you assume a mortgage, you're taking over an existing loan. That loan has a remaining balance. The seller is selling the home for a price that is almost certainly higher than what's left on the loan.

The difference between the sale price and the loan balance is the equity gap. That gap is your responsibility. You cover it out of pocket, through additional financing, or some combination of both.

Let's use a real Colorado example.

A home is listed at $400,000. The seller has an FHA loan with a remaining balance of $295,000. The equity gap is $105,000.

You assume the loan at the seller's rate (say, 2.875%) and pick up monthly payments on $295,000. But you still owe the seller $105,000 for the equity they've built. That's the gap.

Why the Gap Is Not the Same as a Down Payment

With a conventional purchase, your down payment goes directly toward the price of the home. A 5% down payment on a $400,000 home means you finance $380,000 and put $20,000 down.

With an assumption, you're not financing the purchase price. You're taking over an existing loan balance, and the gap is what bridges the seller's equity. Depending on the home and how long the seller has owned it, that gap can be large.

In the example above, the equity gap is $105,000 on a $400,000 home. That's effectively 26% of the purchase price. For a buyer expecting a traditional 5% or 10% down payment scenario, this can be a surprise.

But here's the other side of that: the $295,000 you're financing at 2.875% instead of 6.875% saves you more than $1,000 per month. The gap is a one-time cost. The savings are ongoing for the full loan term.

5 Ways Colorado Buyers Cover the Equity Gap

1. Cash

The most straightforward path. If you have savings, the gap can come entirely from cash. No second loan, no complexity. You fund the gap at closing, assume the loan, and move forward.

This is the cleanest option, but it requires having the cash available, which is where buyers get stuck on larger equity gaps.

2. A Second Mortgage (or Bridge Loan)

Some lenders offer a second mortgage specifically sized to cover the equity gap on an assumption. You end up with two loans: the assumed first mortgage at the seller's low rate, and a second mortgage at current rates covering the gap.

The math still works in your favor as long as the second loan is sized appropriately. A $105,000 second at today's rates adds to your payment, but you're still carrying the $295,000 first at 2.875%. The blended cost is usually lower than financing the full $400,000 at current market rates.

3. Down Payment Assistance Programs

Colorado has several down payment assistance programs at the state and county level. Some of these can be stacked with an FHA assumption. If you're income-eligible, this is worth investigating before you rule out a home based on the gap size.

CHFA (Colorado Housing and Finance Authority) is one program worth looking into. Rules change, so verify current eligibility directly.

4. Gift Funds

FHA loans allow gift funds from family members to cover closing costs and down payments. In an assumption scenario, a family member's gift can potentially cover part or all of the equity gap, depending on how the servicer classifies it. This requires clear documentation, but it's a real option for buyers with family who can help.

5. Negotiating with the Seller

In some cases, sellers are motivated enough to offer seller concessions that effectively reduce the gap. This might look like a price reduction or a contribution toward closing costs. It doesn't eliminate the gap, but it can shrink the cash-at-closing number. This is a negotiation, so results depend on the seller's situation.

What the Monthly Savings Look Like

To understand why buyers are willing to work hard to cover the equity gap, look at the math again on that $295,000 assumed loan.

At 2.875%: $1,224 per month (principal and interest). At 6.875%: $1,938 per month (principal and interest).

Monthly savings: $714. Annual savings: $8,568. Savings over 5 years: $42,840. Savings over 10 years: $85,680.

The equity gap is a one-time problem to solve at closing. The savings repeat every month for as long as you own the home.

Situations Where the Gap May Be Too Large

Not every assumable mortgage is a good deal. If the seller has owned the home for many years and built up substantial equity, the gap could be $200,000 or more on a mid-range Colorado home. At that point, the cash requirement starts to resemble buying the home outright.

A good rule of thumb: if the equity gap is manageable (under roughly 25-30% of the purchase price) and the rate differential is wide (more than 2.5 points), the assumption almost always pencils out. If the gap is very large, run the numbers carefully.

Start by Finding the Right Homes

Assumptions only work with FHA and VA loans. To find homes in Colorado where this option is available, you need to search specifically for those loan types.

Browse assumable listings across Colorado at assumableguy.com. If you want to run the numbers on a specific home, calculate your equity gap, or figure out which combination of sources makes the gap workable, contact Ryan Thomson at Keller Williams. The numbers tend to be more favorable than buyers expect once you actually sit down and look at them.

Equal Housing Opportunity.