If you’re here, you’ve likely been searching “semi-inground pool cost” for a while now and keep landing on numbers that don’t match up. You’re starting to wonder if anyone actually knows the answer, or if you’re just supposed to guess and hope.
The truth is, there isn’t one number, because there isn’t one pool type. A semi-inground pool can be a simple 12×24 tucked into a slope, or a fully custom, stone-wrapped centerpiece with a tanning ledge and a built-in bar. Both are semi-inground pools, and both cost very different amounts.
Aloha Pools & Spas has built pools across the Mid-South since 1969, and our O’Fallon, IL location serves the greater St. Louis area, backed by 57+ years in business. This article breaks down what a semi-inground pool costs around the area, what pushes that price up or down, and why the range is so wide.
Cost of Semi-Inground Pools in the St. Louis Area
Quick answer: semi-inground pools in the St. Louis area typically cost $18,000 to $60,000+, depending on size, materials, and customization.
This is a wide range, and we know this. You can make your pool as simple or as elaborate as you please. To get a semi-inground pool estimate before ever meeting with a sales representative, check out our semi-inground pool cost estimator!
What Makes the St. Louis Area Different
Metro-area building comes with more complexity than our more rural locations, and that is reflected in both price and process. Labor and materials run a bit higher here simply because it’s a bigger, busier market, and more of our builds involve navigating a city or subdivision’s specific rules on top of standard county permitting.
Ground conditions matter too. Much of the O’Fallon area and greater St. Louis floodplain sits on flatter land, which is generally friendly for construction. However, drainage needs to be planned carefully around a semi-inground pool’s retaining wall so water has somewhere to go instead of pushing against it.
Another note: this part of the country sits near a well-known fault line. It’s not something to lose sleep over, but many builders add a little extra reinforcement to retaining walls here, just to be safe.
Permitting in the St. Louis Area
This is where the St. Louis area looks the most different from our other markets. Because our coverage spans multiple cities and municipalities on the Illinois side of the river, permitting isn’t a one-size-fits-all process the way it often is in more rural areas. Most cities require a building permit, a site plan with verified setbacks, and a fence or approved barrier around the finished pool.
On top of that, many St. Louis-area neighborhoods are part of an HOA, which can increase the amount of approvals needed and its own set of design rules before you even get to the city’s paperwork. If you’re in a planned community, check your HOA guidelines early, since some have specific requirements for pool style, fencing, or placement.
Our team handles the municipal side of permitting, but it’s worth starting the HOA conversation with your local branch as early as possible.
Why the Price Range Is So Wide
The simple answer? Customization. A semi-inground pool is one of the most flexible products we build. Flexibility means options, and options mean price swings.
A basic semi-inground pool with a simple retaining wall and standard equipment sits at the lower end of our range. But most homeowners don’t stop there. Once people see what’s possible, they start adding things, and every addition changes the number.
Brick and Stone Perimeters
This is one of the most popular upgrades we see on semi-inground pools, and once you see one finished, you’ll understand why. Wrap a semi-inground pool in a brick or stone perimeter, and it no longer looks like a pool tucked into a hillside- it looks like the most glorious in-ground fire pit you’ve ever seen. It’s a striking look, and it’s the upgrade most semi-inground owners in our area choose. Depending on the material and how much of the pool you wrap, this typically adds a few thousand dollars, up to $10,000 or more, to your total project.
Decking
Wood and composite decking are the next most common add-on, giving you a proper place to set up chairs, a grill, and everything else that makes a backyard feel finished. Decking costs vary a lot based on size and material, so talk it through with an independent contractor for a number specific to your yard.
Other Popular Additions
Tanning ledges, extra steps, lighting packages, and water features are all common additions on semi-inground builds. None of these are required, but they’re worth considering while you’re budgeting, since most customers add at least one.
Note About Fences
Most cities and counties require that pool owners have a safety fence. Check with your local policies before building, because some places require fences of a certain height.
What This Means for Your Budget
If you want the simplest version of a semi-inground pool, you’ll be looking at the lower half of our range. If you’re dreaming of a brick-wrapped, fully decked, tanning-ledge version, plan for the upper half, or beyond it. Most of our St. Louis area customers land somewhere in the middle once they’ve picked their must-haves, and budget a little extra for the permitting and HOA steps that come with building in a metro market.
Aloha Has Been Doing This a Long Time
Aloha has been a family-run pool business since 1969, and we’re still one today. Our construction crews include builders with more than a decade of hands-on experience, and every pool we build, semi-inground included, comes with our 5-year warranty.
We know how to work with floodplain soil, tight suburban lots, and the extra permitting layers that come with a metro market, backed by over 57 years of building pools across the region.
Frequently Asked Questions
How much does a semi-inground pool cost in the St. Louis area? Semi-inground pools in the St. Louis area typically run $18,000 to $60,000 or more, depending on size, materials, and customization.
Why is the price range for semi-inground pools so wide? Semi-inground pools are highly customizable. A basic build with a simple retaining wall sits at the lower end, while upgrades like brick perimeters, decking, and tanning ledges push the price toward the higher end.
Do I need a permit for a semi-inground pool in the St. Louis area? Yes- and it varies more here than in our other markets. Most cities require a building permit, a site plan, and an approved fence or barrier, and many neighborhoods add their own HOA approval on top of that.
Does building in the St. Louis metro area cost more than building in a rural area? Often, it does. Labor and materials tend to cost more in a larger area, and meeting city and HOA requirements takes extra time and money that a rural build doesn’t have.
Let’s Talk About Your Yard
Every yard is different, and the only way to get a real number is to have one of our reps take a look at yours. If you’re ready to see what a semi-inground pool could look like in your backyard, connect with our O’Fallon team or stop by and see us.
