TikTok Custom Audience Customer File: Format, 1,000-Entry Minimum and How to Clean the List First

A TikTok customer file is a CSV or TXT file, under 1 GB, with a header row such as Email or Phone and at least 1,000 entries. Emails go in lower case with no spaces, and phone numbers go in E.164 (a plus sign, the country code, then the number). Verify your email column first so none of those 1,000-plus entries are addresses that can't match. This post uses TikTok's own pages, create a custom audience with a customer file and the customer file guidelines, read on 9 November 2026.

Format your TikTok file →

What TikTok asks for

From TikTok's help pages:

• File type: CSV or TXT.
• Size: under 1 GB.
• Entries: at least 1,000.
• Header row: names the ID type in each column.
• Accepted headers: Email or Email_SHA256; Phone or Phone_SHA256; MAID, MAID_MD5 or MAID_SHA256. Each header can appear up to 3 times when a file mixes ID types.

Email and phone are the ones most advertisers use. A MAID is a mobile advertising ID (an IDFA on iOS or a GAID on Android), which comes from app data and not from a CRM export, so this post skips it.

Formatting the email column

TikTok's page asks you to remove spaces and convert emails to lower case. If you hash the values yourself, it requires SHA-256. A typical export has trailing spaces from copy-pasted cells, mixed capitals such as [email protected], and sometimes two addresses in one cell. Fix those before anything else. The duplicate email remover and the email list cleaner handle repeats and stray characters.

Formatting the phone column

TikTok asks for E.164: a plus sign followed by the country code and number, for example +14155550132. The page also says numbers without the plus sign are supported, as are numbers without the plus sign and country code. In plain English, TikTok will accept looser formats, but a number that is already complete and clean is the safest thing to hand over. If your list mixes US numbers with others, the phone number formatter adds the country code from the country you pick. We cover the same problem in HubSpot phone number format.

Hashing

TikTok's page says files with original, unhashed values are hashed automatically. If you prefer to hash before the file leaves your computer, the page says hashed email and phone values must use SHA-256, and the guideline page says content must be entirely upper case or lower case before hashing. Rename the headers to Email_SHA256 and Phone_SHA256 when you do. The TikTok formatter has a SHA-256 option that hashes the cleaned value and renames the headers for you. Hashing a value that still has a space or a capital letter in it gives a hash TikTok can't match, so clean first and hash second.

How the upload works

TikTok's page lists these steps:

1. Open TikTok Ads Manager and go to the Tools tab.
2. Choose Audience Manager and click Create Audience.
3. Choose Custom Audience, then Customer File.
4. Upload your file, name the audience and click Confirm.

The page says the audience can take 24 to 48 hours to generate. The guidelines page says TikTok looks for users that match the IDs in your file, builds the audience from the matches, and promptly deletes the uploaded file.

The 1,000-entry minimum, and why list quality matters

TikTok's minimum is 1,000 entries. That number is counted on your file, so the work you do before the upload can push a borderline list over or under the line. Here is the order that keeps you out of trouble:

1. Start with the full export.
2. Remove duplicates and rows with no email or phone.
3. Verify the emails.
4. Count what's left.

If the count after step 4 is under 1,000, you don't have a TikTok customer-file audience yet. Add more customers before you try, rather than padding the file with guesses or unverified addresses. A padded file adds entries without adding people who can match. The page doesn't state a match rate, and we won't either.

Why verify before you upload

An address that bounces belongs to no live mailbox, so it can't be tied to someone's account. Verification sorts your list into three groups:

• Valid: the mailbox accepts mail. Keep the row.
• Invalid: the mailbox doesn't exist. Remove the row from the audience file.
• Risky or unknown: the answer wasn't clear, often because the domain accepts all mail. Keep them if the customer relationship is recent, and consider leaving them out if the address is old and the list is long.

Verification doesn't tell you whether someone has a TikTok account, and TikTok decides who matches. It only removes rows that couldn't match anywhere. Our guide on custom audience match rate and your email list goes through the same idea for ad platforms in general.

A second reason is that the same list is often used for email. If you upload to TikTok from the file you also email, one verification pass serves both. How often to verify an email list gives a schedule, and cold email suppression lists shows how to keep a record of the rows you removed so they don't return in the next export.

A short routine

1. Export customers from your store or CRM.
2. Remove duplicates and blank rows.
3. Verify at /verify. Keep valid, review risky, drop invalid.
4. Format with the TikTok formatter: Email and Phone headers, lower-case emails, E.164 phones, an entry count shown against the 1,000 minimum.
5. Upload in Audience Manager and wait for the audience to build.
6. Repeat each time you refresh the audience, using a freshly verified export.

Consent

A customer file is personal data about people you already have a relationship with. Use only data you collected in a way that allows advertising use, and follow the privacy rules that apply to your customers. This post covers the file format, not legal advice.

Related formatters

If you run the same audience on other platforms, the Google Ads Customer Match formatter and the Facebook custom audience formatter write their own headers from the same export. The LinkedIn version is the Matched Audience formatter. Each platform wants slightly different headers, so don't reuse one file.

Try it on your own list

Upload a sample at /verify. The first 100 checks are free with a Google sign-in, no card.

Pro, $39 a month: Unlimited email verification.* Never metered, never cut off. See pricing.

*Fair use: the first 100,000 checks a month at full speed, then slower, never cut off.