21758Knoxville, MD

Prospecting data for 21758: Knoxville, MD

Name: Prospecting data for 21758: Knoxville, MD
Creator: Prospecting Data
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Zip 21758 in Knoxville, Maryland has about 1,460 homeowners. About 480 have a connected mobile phone and 210 of those are clear of the National Do Not Call Registry.

Data as of 2026-09Frederick County

Absentee owners 21758

Data as of 2026-09

Absentee owners260
Mailable address98%260
Connected mobile8%under 100
Email on file15%under 100
Mobile and DNC clear2%under 100

Rounded floors, not promises.

Who lives here
Population	5,130
Housing units	2,130
Owner occupied	87% of occupied homes
Renter occupied	13% of occupied homes
Median household income	$81,000
Median age	40.6
Built before 1970	39% of homes
Built 2000 or later	26% of homes
Median mortgage payment	$1,840 a month
Time zone	EST
Area code	301

Census figures are rounded ACS 5-year estimates for the zip code tabulation area.

What this means for each channel

Direct mail reaches almost everyone: 98% of 21758 homeowners have a deliverable mailing address. Mail is the only channel with no consent requirement, so it is the floor of any Knoxville campaign.

Calling and texting reach about 33% with a connected mobile, but only 14% once you remove numbers on the National Do Not Call Registry. Texting a cold list also needs prior express written consent under the TCPA, so the DNC-clear figure is a calling figure, not a texting figure. See cold calling laws by state.

Email reaches about 51%. Cold email to consumers is legal under CAN-SPAM with an opt-out and a physical address, but deliverability on purchased consumer email is poor; treat it as a supporting touch.

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