Running ads to a prospecting list: match rates, cost, rules

How a list becomes an ad audience

You upload contacts. The platform matches them to its own user accounts and shows your ads only to the matches. Meta calls the result a Custom Audience. Google calls it Customer Match. Both work as the "air cover" behind the channels in the prospecting how-to guides: ads that make a name familiar before the mailer or call arrives.

Both platforms hash personal data before matching. Hashing turns an email or phone number into a fixed code that cannot be read back. Meta's documentation says "You must hash data as SHA256; we don't support other hashing mechanisms." Google accepts SHA256 hashes or hashes the file for you.

Platform	Matching keys	Notes
Meta	EMAIL, PHONE, FN, LN, CT, ST, ZIP, COUNTRY, DOBY, DOBM, DOBD, GEN, device IDs	Up to 10,000 records per request. More keys per record raise the match rate.
Google	Email, Phone, or First Name, Last Name, Country, Zip; also IP address and device ID	Country and Zip are never hashed. A mailing address file needs all four columns.

Neither platform lists a street address as a key. A mailing list with only names and street addresses therefore matches on name and zip, which is a weaker signal than an email or phone. Add emails or mobile numbers from the same people when you have them. The direct mail how-to covers the address side of that list.

What each platform requires before you upload

Google has the stricter gate. Any policy-compliant advertiser can use Customer Match for Observation and Exclusions. Full Targeting needs a good policy and payment history, 90 days of Google Ads history and more than USD 50,000 in lifetime spend. Google can remove access at any time. Memberships expire after 540 days.

Google's Customer Match policy also limits the data itself:

• Upload only data collected in the first-party context, such as your websites, apps, or stores.
• Your privacy policy must say you share customer data with third parties who work on your behalf.
• Do not upload anyone under 13.
• Do not write ads that imply you know personal information about the viewer.
• Do not use a list that targets an overly narrow audience.

Meta's Custom Audience terms put the burden on you. You state that you have "all necessary rights and permissions and a lawful basis" to use the list, and you must remove anyone who later opts out. The terms mention marketing data licensed from independent parties, so Meta does not bar a licensed list outright. Your license must allow ad matching. Google bars any list you did not collect yourself. The safe default for both: past clients, leads, and callers who gave you their details.

Match rates to expect

Plan on a minority to a majority of the list, and measure your own. Neither Meta nor Google publishes a typical match rate. Google shows a match rate only for uploads of at least 100 rows matched to unique users, so small lists give you no number at all.

Source	Figure	Label
Meta developer docs	None published; "provide multiple keys" to raise it	Platform
Google Ads Help	None published; shown in the account when 100 or more rows match	Platform
Clarigital, 04/05/2026	"40 to 80%" depending on data quality	Vendor-reported

The vendor range fits email and phone lists. Expect the low end or below for name-and-zip lists and for older records. Upload a test list first and read the audience size the platform reports.

Cost

Cost depends on the objective, the vendor sample, and the year. These are 2026 benchmarks that LocaliQ, an ad-software vendor, reports from its own customer accounts; the search figures pool Google and Microsoft Ads. They cover whole campaigns, not list audiences, so use them as a rough planning reference.

Metric, real estate	Meta lead campaigns	Meta traffic	Google search
Cost per click	$1.27	$0.55	$3.22
Click-through rate	4.17%	2.37%	7.61%
Conversion rate	9.95%	not reported	3.70%
Cost per lead	$13.74	not reported	$102.51

Worked example. You budget $1,000 on a Meta lead campaign. At the vendor-reported $13.74 per lead, $1,000 / $13.74 = 72.8 leads. The same $1,000 on Google search at $102.51 per lead gives $1,000 / $102.51 = 9.8 leads. Google search captures people who are already looking. A list audience shows ads to known people on a schedule you set, so judge the two by cost per booked conversation, not cost per click.

Ads as air cover for a mail or call sequence

Run the ads in the gaps between your other touches. The person sees your name before the postcard lands and again after the call. Keep the audience in sync with the sequence: add a record when its first mailer drops and remove it when the person responds, so you stop paying to show ads to your own clients.

• Day 0Upload the list. Start a low-budget awareness ad to the matched audience.
• Day 3Postcard lands. Same name and offer as the ad.
• Day 7First call or text, where consent allows.
• Day 21Second mailer. Refresh the ad creative.
• Day 28Remove responders and bad numbers from the audience. Re-upload.

The multi-channel sequence guide places this in a full cadence. The channel rules sit in the guides for cold email and text messaging.

What good numbers look like

Judge the audience before the ad. These bands are working targets, not published benchmarks, except where a source is shown.

Measure	Weak	Workable	Source
Match rate, email or phone list	Under 40%	40% to 80%	Vendor-reported, Clarigital 04/05/2026
Meta lead cost, real estate	Above $27.39 (all-industry average)	At or below $13.74	Vendor-reported, LocaliQ 2026
Google search lead cost, real estate	Above $102.51	At or below $102.51	Vendor-reported, LocaliQ 2026
List refresh	Over 540 days old	Re-uploaded each campaign	Google Ads Help (membership expiry)

Compliance notes

Four rules apply. Check each before you spend.

1. Platform data terms. Google allows first-party data only. Meta requires rights, permissions, and a lawful basis. Do not upload a purchased list unless its license covers ad matching.
2. Housing special ad category. Customer list audiences are allowed in housing ads, but since March 2025 Meta marks some lists ineligible and requires you to certify compliance; Ads Manager or the API flag an ineligible list. Lookalike and saved audiences are unavailable. Age is fixed at 18 to 65+, gender cannot be chosen, zip codes cannot be targeted, and any location needs a radius of at least 15 miles. Real estate listings and mortgage ads fall in the housing group.
3. State privacy opt-outs. California lets consumers tell a business to stop selling or sharing personal information, and sharing means cross-context behavioral advertising. The business then waits at least 12 months before asking again. Other states have similar opt-outs. See the data broker laws page.
4. No implied knowledge. Google bars ad copy that implies you know personal information about the viewer. Do not write "we saw you own 12 Oak St."

Start with the homeowner list or the new mover list for mail and call. Do not move that file straight into an ad audience without checking rules 1 and 3.

Next step

Use the homeowner counts to size your target area before you plan a campaign. For a count on your own zip codes, request a count ledger.

Questions people ask

Q01Can I upload a purchased mailing list to Facebook ads?

Meta's Custom Audience terms require all necessary rights and permissions and a lawful basis, and they mention data licensed from independent parties. So a licensed list is not barred outright, but your license must cover ad matching. Google is stricter and accepts first-party data only.

Q02Does Google Customer Match accept a list of names and addresses?

Yes, in part. A mailing address file needs four columns: First Name, Last Name, Country, and Zip. Google does not take the street line. Email and phone match better, and Google advises adding as many keys as you can.

Q03How many people do I need in a list to run ads?

Google states no upload minimum, but it shows a match rate only when at least 100 rows match to unique users, and a list needs 100 members added or updated in its window to stay eligible. Meta states no minimum in its developer docs.

Q04Can I use a customer list for real estate ads on Meta?

Yes, with limits. Meta lists Custom Audience inclusion and exclusion as supported in housing ads, but since March 2025 some customer lists are ineligible and the advertiser must certify compliance. Lookalike and saved audiences are unavailable for housing ads.

Q05Do state privacy laws let people opt out of list-based ads?

In California, consumers can ask a business to stop selling or sharing personal information, and sharing means cross-context behavioral advertising. A person who opted out must stay out of your uploaded audiences, and you wait 12 months before asking again.

Sources

1. Google Ads Help, Customer Match overview (membership expires after 540 days, 100 member refresh rule)support.google.com
2. Google Ads Help, Customer Match data formatting (match keys, hashing, match rate display)support.google.com
3. Google Ads Help, Customer Match eligibility (90 days and USD 50,000)support.google.com
4. Google Advertising Policies, Customer Match (first-party data, prohibited uses)support.google.com
5. Meta for Developers, Custom Audiences (schema keys, SHA256, 10,000 per request, multiple keys raise match rate)developers.facebook.com
6. Meta for Developers, Special Ad Category (housing restrictions, customer list eligibility check)developers.facebook.com
7. Meta for Developers, 2024 out-of-cycle changes (customer list eligibility in housing ad sets from March 2025, certification)developers.facebook.com
8. Meta Custom Audience Terms (rights, lawful basis, opt-outs, licensed data)facebook.com
9. LocaliQ, Facebook advertising benchmarks 2026 (vendor-reported, real estate lead campaigns)localiq.com
10. LocaliQ, search advertising benchmarks 2026 (vendor-reported, Google Ads)localiq.com
11. Clarigital, Meta Custom Audiences (vendor-reported match rate, April 2026)clarigital.com
12. California Attorney General, CCPA (opt out of sale or sharing)oag.ca.gov