In September 2026, the median sales price in Slidell's 70458 ZIP code rose 18.5% from a year earlier, to $272,500. Over the same period, the median for the first nine months of 2026 in that ZIP fell 2.1%, to $225,000. Both figures come from the same one-page report, the New Orleans Metropolitan Association of REALTORS® Local Market Update for 70458, current as of October 7, 2026.
In Slidell, the monthly median mostly tracks which homes happened to close that month. The figures that describe a buyer's position are months of supply, the share of list price sellers actually receive, and the new homes being permitted a few streets from the resale listings. On those figures, Slidell gives buyers more room than any Mandeville or Covington ZIP code in the September 2026 reports.
What a seller in 70460 actually received
Start with the figure that matters at the closing table. In Slidell's 70460 ZIP, the area that includes addresses such as Belair, homes that closed in September 2026 sold for 94.2% of list price on average, down from 97.7% in September 2025. Days on market rose from 57 to 96. On a home listed at $220,000, a 94.2% ratio would mean a sale price of about $207,240.
That gap may still understate the discount. Under each ZIP-level table, the association prints this note:
"Does not account for sale concessions and/or downpayment assistance. | Percent changes are calculated using rounded figures and can sometimes look extreme due to small sample size."
If a seller agrees to the asking price and then covers some of the buyer's closing costs, the report records a full-price sale. So the 94.2% figure is the most a seller could have kept, and the real number may be lower. It also comes from only 16 closings in September. Over the first nine months, 70460's ratio was 96.5% and its median was $194,000, down 8.2% from the same period in 2025. The year-to-date numbers point the same way as September, just more gently.
Why 70458's median jumped in a softening month
The same small-sample problem explains the 18.5% jump in 70458. September closings in that ZIP rose from 31 to 44, while pending sales, the contracts signed that month, fell from 47 to 38. A closing records a deal agreed weeks earlier. So September's closings mostly reflect summer contracts, and the drop in September contracts is what will show up in later reports.
When only 44 homes sell, a few larger or newer homes closing in the same month can lift the median without any single house gaining value. The year-to-date figures, built from 351 closings, put 70458's median at $225,000 and its average at $249,251, down 7.1%. This is the ZIP that includes Eden Isles addresses. Across the year, its price level has been flat to slightly lower, and that is the figure to plan around.
Supply, measured in months
Months of supply is the number of months it would take to sell every active listing at the current pace of sales. It is the clearest single gauge of who has leverage, and it is where Slidell differs most from the rest of St. Tammany Parish.
| ZIP code, September 2026 | Months of supply | Days on market | % of list received | YTD median |
|---|---|---|---|---|
| 70458, Slidell | 6.2 | 62 | 96.7% | $225,000 |
| 70460, Slidell | 5.3 | 96 | 94.2% | $194,000 |
| 70461, Slidell | 4.8 | 90 | 98.5% | $265,000 |
| 70433, Covington | 3.9 | 67 | 97.3% | $349,900 |
| 70435, Covington | 3.8 | 66 | 99.0% | $325,000 |
| 70448, Mandeville | 3.4 | 47 | 95.5% | $385,000 |
| 70471, Mandeville | 3.4 | 67 | 96.7% | $433,000 |
| St. Tammany Parish | 4.3 | 70 | 97.0% | $301,570 |
All of these are the association's September 2026 Local Market Updates for all residential properties. Across the parish, supply tightened over the year, from 5.3 months in September 2025 to 4.3, as inventory fell 10.4% to 1,402 homes. Covington's 70433 tightened the most. Its inventory fell 20.3% to 212 homes and its supply dropped from 6.1 months to 3.9.
Slidell's 70458 barely changed. It had 244 active listings in September, compared with 245 a year earlier, and 6.2 months of supply. New listings there rose 21.8% for the month and 7.8% for the year. Sellers kept listing homes at a steady pace while inventory elsewhere on the Northshore shrank. So a buyer who moves between Mandeville and Slidell is also moving from a market with 3.4 months of supply to one with nearly twice that.
The new homes competing with Slidell's resale listings
The 70461 numbers look more balanced at first. Supply there fell from 5.7 months to 4.8, and September sellers received 98.5% of list price. What the report leaves out is how much new construction is going up in that ZIP.
St. Tammany Parish's weekly permit reports show D.R. Horton building single-family homes through the late summer and fall of 2026 in two 70461 subdivisions:
- Lakeshore Villages Phase 6B: a permit at 3303 Tide Wind Drive, issued August 10, 2026, and another at 3208 Tide Wind Drive, issued October 7, 2026, for 2,387 square feet at a permit valuation of $179,025
- Lakeshore Villages Phase 12A: two permits on Rose Gentian Drive issued October 7, 2026, for 1,884 and 1,810 square feet at valuations of $141,300 and $135,750
- Bonterra Phase 3: a permit at 40563 Cara Mae Street, issued September 15, 2026
The October 5–11 report lists these alongside other permits from around the parish. A permit valuation estimates construction cost, not a sale price. The builder's own marketing for Lakeshore Villages lists homes from $169,900 and advertises a "Special Interest Rate" on select homes, without stating the rate or its terms. Builder pricing and promotions change often. Even so, the offer shows what an owner of a resale home in 70461 is competing against.
This connects back to the association's footnote. Builders often compete through financing incentives, and resale sellers often respond with closing-cost credits, which the list-to-sale ratio does not capture. A 98.5% figure in a ZIP with active new construction tells a buyer less than the same figure would in a ZIP with none. Before deciding how much 70461's high ratio says about competition, a buyer should ask what concessions comparable sales included.
The next lots coming
More supply is in the pipeline inside the city limits. On July 20, 2026, the Slidell Planning Commission voted 4–0 to recommend a preliminary plat for 52 lots on 21.16 acres at 1450 Gause Boulevard West, zoned R3 High Density Residential, and sent it to the City Council with a favorable recommendation. The project appears in city planning records as Sagefield. A preliminary plat approves a layout, not houses. Its importance for a buyer is the direction of supply. Covington's inventory has been falling, while Slidell's has held steady and the city is still adding lots.
For a buyer, that makes Slidell the Northshore market where time is most likely to be on their side. For a seller, the competition is less the house next door than the new home down the road with a financing offer attached.
Questions buyers ask about these numbers
Does a rising monthly median mean Slidell prices are going up? Not on its own. In 70458, a single month's median rose 18.5% while the year-to-date median fell 2.1%, and contracts signed in September dropped 19.1%. The nine-month figure, built from hundreds of sales, is the steadier guide.
Why do the three Slidell ZIP codes look so different? They have different supply and different new construction. In September 2026, 70458 had 6.2 months of supply, 70460 had the longest days on market at 96, and 70461 had active builder permits in Lakeshore Villages and Bonterra. A Slidell-wide average would hide all three.
Does percent of list price received reflect what the seller kept? The association states that its price and list-ratio figures do not account for sale concessions or down payment assistance. Closing-cost credits and builder incentives can sit outside the number entirely. This post is general market information, not legal, tax or financial advice, so buyers weighing a financing offer should confirm the terms with their lender.
If you are comparing a Slidell ZIP code with Mandeville or Covington, or deciding how to price against new construction in 70461, Jennifer Rice and Lauren Mendheim can walk you through the closed sales, concessions included, behind your street's numbers. Start with a complimentary home valuation built on the September reports and the permits filed near you.
