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Almost never for the prints themselves: a fax turns fingerprint ridges into a blurry black-and-white image that automated matching systems cannot read, so agencies that process background checks require the original card or a proper electronic submission. A fax can still carry the cover paperwork around the card, but the card itself should travel by mail or in person.
Fingerprint matching depends on fine detail: ridge endings, splits, and the exact spacing between ridges. A fax machine scans at a low resolution, converts everything to black or white with no gray in between, and then squeezes the image through a phone line. Thin ridges merge into blobs, light ridges vanish, and smudges that a human eye could ignore become false features. Automated fingerprint identification systems score image quality before they even try to match, and a faxed image almost always scores too low to process. Even a trained examiner working by eye struggles with a faxed card, because the fax process destroys exactly the detail that separates one person's prints from another's.
Most agencies that run fingerprint-based checks accept two forms and little else. The first is the original inked card, usually the standard FBI applicant card or a state equivalent, mailed to the processing center or handed in at an enrollment site. The second is a live scan, where a technician rolls your prints on a digital scanner that captures them at high resolution and sends them electronically. Some agencies now accept prints taken at approved private enrollment centers, which scan and transmit them for you. What they share is a chain of quality: the prints are captured cleanly, checked on the spot for smudges or missing fingers, and transmitted without the degradation a fax adds. A photocopy or a fax of a card breaks that chain, which is why instructions for fingerprint cards so often say "do not fax" in plain language.
| Method | Accepted for matching? | Why |
|---|---|---|
| Original inked card by mail | Yes | Full ridge detail preserved on paper |
| Live scan at an enrollment center | Yes | High-resolution digital capture, checked on the spot |
| Scan or photo emailed as a file | Sometimes, if the agency says so | Quality varies; only when the agency invites it |
| Fax of the card | Almost never | Resolution loss destroys the detail matching needs |
The card rarely travels alone. Background check packets usually include an application form, a consent and release form, and sometimes a payment form. Those text pages fax fine, and some agencies accept them by fax while the card itself goes by mail. If you split the packet this way, put a cover sheet on the fax that names the applicant, lists what is being faxed, and states that the original card is coming separately by mail, with the mailing date. That keeps the file from being marked incomplete when the fax arrives without the card. Confirm the split is allowed before you send anything: a few agencies want the whole packet together, and a partial fax can create confusion rather than speed.
Sometimes, but only when the agency explicitly invites electronic submissions. A flatbed scan at high resolution preserves far more detail than a fax, and some state agencies and private background check firms now accept scanned cards uploaded through a portal. The key is that the agency controls the quality standard: it will specify resolution, file format, and whether the scan must come from an approved vendor. A scan you make at home and email on your own initiative is a gamble. If the agency's instructions do not mention scans, assume the original card is required, and do not let a rejection notice be your first sign that the scan was not good enough.
Rejections usually come from the card itself, not the delivery method. Have prints taken by someone trained to do it, such as a police department or an enrollment center, rather than rolling your own at home. Dry or lotioned hands cause smudges and faint ridges, so wash and dry your hands first and skip hand lotion that day. Check that every finger box is filled, including thumbs, and that the card carries your full name, date of birth, and any agency reference number exactly as instructed. If a card comes back rejected, the agency usually allows one resubmission without a new fee, but the clock restarts, which is why getting it right the first time matters more than getting it sent fast.
Fax through LetterAgent is currently in testing, and it is not a service to promise for a same-day deadline. When it is available, you send a fax by asking your AI assistant: you get a per-fax quote with the page count verified, you approve the exact total, and you pay once through Stripe. LetterAgent faxes go to US and Canadian numbers only. That flow works for the cover forms around a fingerprint card, but it does not change the basic rule: the card itself should go by mail or live scan, not by fax, through any service.
Ready to fax it? Fax with LetterAgent: describe it to your AI assistant, approve the exact quoted price, and it is sent.
LetterAgent is a working name. Prices include print, postage, and our service fee. US prices in USD, Canadian prices in CAD (Canadian prices exclude applicable sales tax, added at checkout). Currently in private testing.
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