ZIP 21158

21158 is one of 9 ZIP codes that lie mostly in Carroll County, MD.

Shaded by typical home value, it ranks 4 of the 9 with a value.

2 school locations in 21158: 2 elementary.

In alphabetical order: Runnymede Elementary, Westminster Elementary. Locations only — no ratings are shown here.

In January 2000 the typical home in 21158 was worth $164,553.

Values peaked at $470,700 in July 2026. The latest reading is the peak.

As of August 2026: $470,619, +1.1% over twelve months.

Start with the typical home: $470,619. Put 20% down and borrow $376,495 at 7.40%, the 30-year fixed average as of October 8, 2026.

That is $2,607 a month in principal and interest.

The median household here earns $108,795 a year, $9,066 a month. So the payment takes 28.8% of income — rated “stretched” (Lotvox ZIP bands: under 28% affordable · 28–36% stretched · 36%+ severe).

The line holds today's rate fixed and moves only the price: at that rate, the same share was 10.1% in 2000.

Take the typical home's price each month, borrow 80% at that month's actual 30-year average rate: in January 2000 (8.21%) the payment was $985.

In December 2020, with rates at 2.68%, it was $1,162.

By August 2026, at 6.67%, it was $2,421 — +108% since December 2020, while the home's value moved +31%.

Reported values rose +186% since January 2000.

General prices (CPI-U) rose +97% over the same span.

Divide one by the other: in August 2026 dollars, the 2000 home was worth $324,762. So the real change is +45%, not +186%.

21158: +186% since January 2000.

Carroll County: +187% since January 2000.

Maryland: +180% since January 2000 — 21158 ran ahead of it by 6 points.

Owning the typical home costs about $3,077 a month once taxes and insurance (estimated at 1.2% of price a year) are added. Renting runs about $1,925 a month.

Price divided by a year's rent: 20.4. Lotvox reads under 15 as favoring buying and 20 or more as favoring renting.

Picture the Listings Flow Ladder as a basin: new listings pour in from the faucet, the homes for sale are the water, and closed sales run out the drain. Coming in — new listings: about 28 a month (Redfin, 3-month rolling data through August 2026). That is 82% of the 2015–2019 level for the same months.

On the shelf — homes for sale at the end of the period: 44.

Going out — closed sales: about 23 a month. That is 67% of the 2015–2019 level for the same months.

The ladder: homes for sale ÷ monthly sales = 1.9 months of supply — below the 4–6 month range Lotvox treats as balanced. In the basin, that is the water level against the shaded balanced band.

The net reading: about 5 more homes came on than sold each month, so inventory is growing. The basin is filling.

Homes sold: about 23 a month in August 2026 (Redfin).

The 2015–2019 level for the same month was 28 — so sales ran at 82% of it, and below it in 23 of the last 24 months.

Across Carroll County, builders pulled permits for 153 new homes in 2025.

Of those, 100% were in 1-unit buildings (the Census Bureau's category for detached and attached single homes).

This ZIP sits in Carroll County. IRS tax returns for 2022-2023: among the ten counties sending the most households, 2,761 moved in. Among the ten receiving the most, 2,272 moved out.

Net across those counties: +489 households. Beside it, homes for sale in this ZIP: 44 in June 2026.

Most arrivals came from Baltimore, MD (842 households); most departures went to Baltimore, MD (593).