St. Louis, Where the Flood-Zone Rule Bites Hardest
Program and regulatory figures verified September 26, 2026. Details change; confirm your scenario with us.
St. Louis has the widest county footprint of any Missouri MHDC area and the most floodplain. Both facts change how you shop here.
The footprint
MHDC's St. Louis MSA row covers Franklin, Jefferson, Lincoln, St. Charles, St. Louis City, St. Louis County and Warren counties. St. Louis City is listed separately from St. Louis County, as it should be, they are legally distinct.
The exclusion is unusual. Rather than dropping a whole county for a lower limit, MHDC excludes "the Sullivan City part of Crawford County" and gives the reason as administrative ease. Sullivan straddles a county line; MHDC has simply declined to split it.
| 1–2 persons | 3 or more | |
|---|---|---|
| Non-targeted | $113,500 | $130,525 |
| Targeted / Next Step | $136,200 | $158,900 |
| Difference | $22,700 | $28,375 |
The flood-zone rule in this metro
Cornerstone's approved MHDC guidance states that all variations of properties located within flood zones A and V are ineligible. St. Louis is where that rule removes the most housing from the map.
The Mississippi runs the eastern edge, the Missouri comes in at the north-west of the metro, and the Meramec cuts through Jefferson and St. Louis counties with a long record of flooding. There is ordinary, affordable, otherwise-eligible inventory inside mapped zones in all three corridors.
The practical rule: check the flood zone before the second showing. The check costs nothing and takes a minute, and it prevents the worst version of this, which is finding out in underwriting after you are under contract. Property rules.
The market
St. Louis's typical home value was $275,704 in August 2026, up 3.4% year over year. That is the fourth-highest in Missouri, behind Kansas City, Columbia and Warrensburg, and it leaves a great deal of room under the $566,354 price cap.
Against that price base, 4% of the mortgage amount is a real contribution to closing rather than a token. Size it.
City and county are different answers
For income limits they are the same row. For targeted-tract status they are not remotely the same, and St. Louis City contains a substantial number of tracts that qualify while much of the county does not.
That matters for one group specifically: repeat buyers who want First Place. For everyone else Next Step reaches the same limits without the lookup. Targeted tracts.
A note for duplex buyers
St. Louis has more two-family housing stock than most Missouri markets, and MHDC treats it well: owner-occupied two-unit properties are eligible, the two-family price limit is $725,146 non-targeted or $886,289 on Next Step, and rental income from the second unit is excluded from the household income calculation for First Place even where it is used to qualify.
That combination is genuinely favourable and very few buyers know about it. The income exclusions.
The full test · the forgiveness schedule · send us an address.
Frequently asked questions
What is the MHDC income limit in St. Louis?
$113,500 for a one to two person household and $130,525 for three or more in the non-targeted column, rising to $136,200 and $158,900 on the targeted and Next Step column. The St. Louis MSA row covers Franklin, Jefferson, Lincoln, St. Charles, St. Louis City, St. Louis County and Warren counties, effective May 1, 2026.
Why does MHDC exclude part of Crawford County from St. Louis?
MHDC's sheet excludes the Sullivan City part of Crawford County and gives the reason as administrative ease. Sullivan straddles a county line, and rather than split the city across two income rows MHDC has left that portion out of the St. Louis MSA row. It is the only one of MHDC's four exclusions not driven by a lower income limit.
Does the flood zone rule matter in St. Louis?
More than anywhere else in Missouri. Properties in flood zones A and V are ineligible in all variations, and the St. Louis metro sits against the Mississippi, the Missouri and the Meramec, with ordinary affordable inventory inside mapped zones in all three corridors. Checking the flood zone before the second showing is the practical step.
Can I buy a two-family property in St. Louis with MHDC assistance?
Yes. Owner-occupied one- or two-unit duplexes are eligible, the two-family purchase price limit is $725,146 non-targeted and $886,289 on Next Step, and MHDC excludes anticipated rental income from the second unit from the household income calculation for First Place even where it is used as qualifying income. St. Louis has more of this stock than most Missouri markets.
Are St. Louis City and St. Louis County treated the same by MHDC?
For income limits, yes, both sit in the same St. Louis MSA row. For targeted-area status, no: designation is by census tract, and the city contains substantially more qualifying tracts than much of the county. That distinction only matters for a repeat buyer who wants First Place, since Next Step reaches the same limits without any tract lookup.
Mike Certo · NMLS #260555 · Cornerstone First Mortgage NMLS #173855 · Equal Housing Lender. Educational content about financing, not a loan commitment and not legal or tax advice. MHDC program terms, income limits and purchase price limits are set by the Missouri Housing Development Commission and change; figures here carry the date we verified them against MHDC's published documents. MHDC down payment assistance is a forgivable second loan, not a grant, and selling or refinancing inside ten years can require repaying all or part of it. Loans are subject to borrower and property qualification.