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Yes, if the store accepts faxes. Most eyewear shops, especially online retailers with a fax line, will take a faxed prescription. The copy must show your full prescription, the exam date, and the prescriber's details clearly, or the store will ask you to resend it.
Online eyewear sellers often give you a choice: upload a photo, type the numbers in yourself, or have your eye doctor send the prescription directly. Fax fits the third option, and it is useful when you have a paper prescription in hand and no scanner nearby. The catch is legibility. A prescription is a grid of small numbers, and a blurry fax turns a simple order into a back-and-forth.
An eyeglass prescription lists sphere, cylinder, and axis for each eye, plus an add power if you need bifocals or progressives. It may also list pupillary distance, the space between your pupils, which the store needs to centre the lenses correctly. If your prescription does not include pupillary distance, ask the store whether they can measure it another way or whether you need to get it from your eye doctor first.
The store also needs the prescriber's name and practice, the exam date, and your full name. A page with numbers but no name or date looks like anyone's prescription, and a careful store will not fill it. Include the whole page, not a cropped photo of the number grid. Cropped copies are the most common reason faxed prescriptions get rejected.
| Field | Why the store needs it | What goes wrong if it is missing |
|---|---|---|
| Sphere, cylinder, axis per eye | Defines the lens power | Order cannot be made at all |
| Add power | Needed for bifocal and progressive lenses | Reading portion left out or guessed |
| Pupillary distance | Centres the lenses on your eyes | Glasses may feel off even with the right power |
| Exam date | Shows the prescription is current | Store may refuse an expired prescription |
| Prescriber details | Lets the store verify the prescription | Order held until the store can confirm it |
Rules vary by state and province, and the expiry printed on the prescription is the first thing to check. In many US states, an eyeglass prescription expires after one or two years from the exam date, and some states set the period by law rather than leaving it to the doctor. In Canada, expiry rules differ by province and by the prescribing professional. If the date on your copy has passed, the store will usually ask for a new exam rather than fill the old numbers.
Do not assume a faxed copy extends the expiry. The date that matters is the exam date on the original prescription, not the date you faxed it. If you are close to expiry, order before it lapses or book a new exam first. A store that fills an expired prescription is taking a risk with your vision, and most will not do it.
Either works, but a fax from the doctor's office carries more weight when the store wants to verify the prescription. Stores sometimes call the prescriber to confirm the numbers, and a fax that arrived from the clinic's own number makes that check simple. If you fax it yourself, include a cover sheet with your name, order number if you have one, and a phone number where the store can reach you.
Watch the minus signs. On a fax, a minus sign in front of a sphere value can fade into a smudge, and a minus read as a plus would flip the lens entirely. Before sending, look at your copy and confirm every minus sign is dark and clear. If any number is doubtful, ask the eye doctor's office to send a fresh copy instead of guessing.
Many small optical shops never set up a fax line, and some online sellers dropped fax when uploads became standard. In that case, a clear phone photo of the full prescription page usually works as an upload. Hold the page flat, photograph it in bright light without flash glare, and check that every number is readable before you send it. A scan from a library or office supply store is even better.
Keep your original prescription somewhere safe either way. You may need it again for a second pair, a replacement, or a different seller, and getting a copy from the doctor's office later takes time. Treat the paper copy like the prescription itself, because in practice, it is.
LetterAgent faxing is available in testing for US and Canadian fax numbers, and it does not accept inbound faxes. You ask your AI assistant, get a per-fax quote with the page count verified, approve the exact total, and pay once through Stripe. Because fax is still in testing, do not rely on it for a rush order without confirming the store received a readable copy.
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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