ZIP 20817 vs ZIP 20854

20817 is one of 48 ZIP codes that lie mostly in Montgomery County, MD.

Shaded by typical home value, it ranks 2 of the 36 nearby ZIPs shown.

10 school locations in 20817: 7 elementary, 2 middle, 1 high.

In alphabetical order: Ashburton Elementary, Bannockburn Elementary, Bradley Hills Elementary, Burning Tree Elementary, and more on the ZIP page. Locations only — no ratings are shown here.

20854 is one of 48 ZIP codes that lie mostly in Montgomery County, MD.

Shaded by typical home value, it ranks 3 of the 36 nearby ZIPs shown.

9 school locations in 20854: 6 elementary, 2 middle, 1 high.

In alphabetical order: Bells Mill Elementary, Beverly Farms Elementary, Cabin John Middle, Cold Spring Elementary, and more on the ZIP page. Locations only — no ratings are shown here.

In January 2000 the typical home in 20817 was worth $444,235.

Values peaked at $1,291,751 in April 2025. The latest reading is −1.1% from that peak.

As of August 2026: $1,277,873, +0.5% over twelve months.

Start with the typical home: $1,277,873. Put 20% down and borrow $1,022,298 at 7.40%, the 30-year fixed average as of October 8, 2026.

That is $7,078 a month in principal and interest.

The median household here earns $240,104 a year, $20,009 a month. So the payment takes 35.4% 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 12.3% 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 $2,660.

In December 2020, with rates at 2.68%, it was $3,273.

By August 2026, at 6.67%, it was $6,574 — +101% since December 2020, while the home's value moved +26%.

Reported values rose +188% 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 $876,744. So the real change is +46%, not +188%.

20817: +188% since January 2000.

Montgomery County: +182% since January 2000.

Maryland: +180% since January 2000 — 20817 ran ahead of it by 7 points.

Owning the typical home costs about $8,356 a month once taxes and insurance (estimated at 1.2% of price a year) are added. Renting runs about $3,227 a month.

Price divided by a year's rent: 33.0. Lotvox reads under 15 as favoring buying and 20 or more as favoring renting.

In January 2000 the typical home in 20854 was worth $481,673.

Values peaked at $1,277,206 in May 2025. The latest reading is −0.9% from that peak.

As of August 2026: $1,266,150, +0.1% over twelve months.

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 $2,884.

In December 2020, with rates at 2.68%, it was $3,157.

By August 2026, at 6.67%, it was $6,514 — +106% since December 2020, while the home's value moved +30%.

Reported values rose +163% 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 $950,631. So the real change is +33%, not +163%.

20854: +163% since January 2000.

Montgomery County: +182% since January 2000.

Maryland: +180% since January 2000 — 20854 ran behind it by 18 points.

Owning the typical home costs about $8,279 a month once taxes and insurance (estimated at 1.2% of price a year) are added. Renting runs about $4,488 a month.

Price divided by a year's rent: 23.5. 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 51 a month (Redfin, 3-month rolling data through August 2026). That is 92% of the 2015–2019 level for the same months.

On the shelf — homes for sale at the end of the period: 142.

Going out — closed sales: about 47 a month. That is 73% of the 2015–2019 level for the same months. The drain is drawn 24% narrower: the share of homes for sale that sell each month is 76% of its 2015–2019 level.

The ladder: homes for sale ÷ monthly sales = 3.0 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 4 more homes came on than sold each month, so inventory is growing. The basin is filling.

Homes sold: about 47 a month in August 2026 (Redfin).

The 2015–2019 level for the same month was 47 — so sales ran at 100% of it, and below it in 15 of the last 24 months.

Across Montgomery County, builders pulled permits for 1,411 new homes in 2025.

Of those, 57% were in 1-unit buildings (the Census Bureau's category for detached and attached single homes).

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 54 a month (Redfin, 3-month rolling data through August 2026). That is 80% of the 2015–2019 level for the same months.

On the shelf — homes for sale at the end of the period: 114. That is 50% of the 2015–2019 level for the same months.

Going out — closed sales: about 52 a month. That is 72% of the 2015–2019 level for the same months.

The ladder: homes for sale ÷ monthly sales = 2.2 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 2 more homes came on than sold each month, so inventory is growing. The basin is filling.

Homes sold: about 52 a month in August 2026 (Redfin).

The 2015–2019 level for the same month was 48 — so sales ran at 108% of it, and below it in 13 of the last 24 months.

Across Montgomery County, builders pulled permits for 1,411 new homes in 2025.

Of those, 57% were in 1-unit buildings (the Census Bureau's category for detached and attached single homes).

This ZIP sits in Montgomery County. IRS tax returns for 2022-2023: among the ten counties sending the most households, 12,327 moved in. Among the ten receiving the most, 15,047 moved out.

Net across those counties: −2,720 households. Beside it, homes for sale in this ZIP: 142 in June 2026.

Most arrivals came from Prince George's, MD (3,735 households); most departures went to Prince George's, MD (3,823).

County assessor records list 58 properties with a market value here. Their average assessed market value is $470,250; the typical home value is $1,277,873.

The assessor average sits −63.2% from the market figure — an average against a typical value, so treat it as a check, not a verdict.

This ZIP sits in Montgomery County. IRS tax returns for 2022-2023: among the ten counties sending the most households, 12,327 moved in. Among the ten receiving the most, 15,047 moved out.

Net across those counties: −2,720 households. Beside it, homes for sale in this ZIP: 114 in June 2026.

Most arrivals came from Prince George's, MD (3,735 households); most departures went to Prince George's, MD (3,823).

County assessor records list 85 properties with a market value here. Their average assessed market value is $527,300; the typical home value is $1,266,150.

The assessor average sits −58.4% from the market figure — an average against a typical value, so treat it as a check, not a verdict.