Fax is still one of the ways prescriptions travel from doctors' offices to pharmacies. But it is more tightly regulated than almost any other kind of fax, and the rules depend on who is sending it and what drug it is for. A patient faxing a photo of their own prescription will usually be turned away. A practice faxing a Schedule II opioid prescription is restricted to a few narrow cases.

This guide explains faxing a prescription to a pharmacy: who is allowed to send one, the federal rules for controlled substances, how electronic prescribing mandates change the picture, and how to find the right pharmacy fax number. It is general information, not medical or legal advice; pharmacists and state boards of pharmacy have the final word.

  • Prescriptions come from the prescriber, not the patient
  • Controlled substances follow federal fax rules, with Schedule II the strictest
  • E-prescribing mandates increasingly replace fax entirely

Table of Contents

Who can fax a prescription

A prescription is an instruction from a prescriber to a pharmacist. That is why faxed prescriptions are expected to come from the prescriber's office.

Federal controlled substance rules make this explicit: they describe a faxed prescription as one "transmitted by the practitioner or the practitioner's agent" to the pharmacy. Pharmacies apply similar expectations to non-controlled drugs, and state pharmacy laws set the details. Mail-order pharmacies say so directly:

  • Express Scripts tells members to have their doctor call 1-888-327-9791 for faxing instructions, and states that faxes can only be accepted from a doctor's office.
  • CVS Caremark Mail Service Pharmacy states on its FastStart prescriber fax form that the fax will only be accepted when sent from a prescriber's secure fax line.

So if you are a patient holding a paper prescription, faxing it yourself is generally not the answer. See what patients can do instead.

Federal rules for controlled substances

The Drug Enforcement Administration's regulations (21 CFR Part 1306) set out when controlled substance prescriptions can be faxed. State laws can be stricter.

Schedule II (for example, many opioids and stimulants):

  • A prescriber or agent may fax a Schedule II paper prescription to a pharmacy, but the original, manually signed prescription must be presented to the pharmacist before the drug is actually dispensed. The fax lets the pharmacy prepare; it does not replace the original.
  • The fax itself serves as the original prescription only in three situations:
    • Narcotic prescriptions to be compounded for direct administration by infusion (such as intravenous or subcutaneous)
    • Prescriptions for a resident of a long-term care facility
    • Narcotic prescriptions for a patient enrolled in a hospice care program, which the prescriber or agent must note on the prescription

Schedules III, IV, and V:

  • A pharmacist may dispense based on a paper prescription signed by a practitioner, a fax of a signed paper prescription transmitted by the practitioner or the practitioner's agent, an electronic prescription meeting DEA requirements, or an oral prescription promptly reduced to writing by the pharmacist.

Non-controlled drugs are governed mainly by state law and pharmacy policy. Many pharmacies accept faxed prescriptions from prescribers' offices, and some mail-order forms, such as CVS Caremark's FastStart form, are limited to non-controlled drugs.

Prescription type Fax allowed under federal rules?
Schedule II Fax in advance only; original must be presented before dispensing, except infusion compounding, long-term care residents, and hospice patients
Schedules III to V Yes, when transmitted by the practitioner or agent
Non-controlled Set by state law and pharmacy policy; commonly accepted from prescribers

E-prescribing requirements

Electronic prescribing is steadily replacing fax:

  • Medicare Part D. Section 2003 of the SUPPORT Act requires that Schedule II to V controlled substances under Medicare Part D be prescribed electronically, with exceptions. Under the CMS EPCS Program, prescribers must transmit at least 70 percent of their Part D controlled substance prescriptions electronically each measurement year, after exceptions. Pharmacies have no compliance requirement under the program; it applies to prescribers.
  • State mandates. Many states have their own e-prescribing requirements, which CMS notes are separate from its program. Check your state board of pharmacy or medical board for the rule that applies.

For a prescriber, that means a fax may be permitted by DEA rules and still not be the right channel because of a state or Medicare requirement.

Finding a pharmacy fax number

  • Retail pharmacies (CVS, Walgreens, and others). There is no national prescription fax number. Each store has its own fax line, and prescribers typically get it by calling the store. Do not use a number from a third-party directory.
  • CVS Caremark mail order. The FastStart New Prescription Fax Form gives 1-800-378-0323 for non-controlled maintenance prescriptions, sent from the prescriber's secure fax line, or e-prescribe to CVS Caremark Mail Order Electronic (NCPDP ID 0322038). The form we checked appears to be several years old, so confirm the number with Caremark before relying on it.
  • Express Scripts home delivery. The prescriber calls 1-888-327-9791 for faxing instructions.
  • Prior authorization for drugs is a separate line. CVS Caremark lists 1-855-633-7673 for Medicare Part D prior authorization requests. See our prior authorization guide.

Verified October 2026 against caremark.com and express-scripts.com.

What patients can do instead

If you need a prescription filled somewhere new:

  • Ask the prescriber to send it electronically or by fax to the pharmacy of your choice.
  • Transfer it. Ask the new pharmacy to transfer the prescription from the old one. CVS, for example, offers an online transfer and says you mainly need your prescription label. Some controlled substance prescriptions can only be transferred once.
  • Take the paper prescription in person if you have one.

Patients do still fax pharmacy-adjacent paperwork: insurance appeals for a denied drug, medical records requested by a specialist, or forms a prior authorization requires. Our guides to faxing insurance companies and medical records cover those.

For prescribers' offices without a fax machine, an online service sends the same transmission over the phone network. You can send a fax online for a one-time payment, with no subscription. Bear in mind that some pharmacies, such as CVS Caremark's mail-order service, only accept prescriptions from a prescriber's own secure fax line, so confirm what the receiving pharmacy accepts first.

Privacy and HIPAA

Prescriptions are health information. HHS guidance confirms that health care providers may share patient information for treatment by fax, as long as they use reasonable safeguards, such as confirming the fax number with the recipient when it is not one they use regularly.

Faxio stores uploaded documents encrypted and uses them only to render and transmit your fax, as described in our privacy policy.

Faxing a prescription to a pharmacy comes down to three questions: is the sender the prescriber's office, does federal and state law allow fax for this drug, and does the pharmacy accept it from that line? When all three are yes, fax works. When any is no, e-prescribing or a transfer is the better route.

Send a fax online →

Frequently asked questions

Can I fax my own prescription to a pharmacy?

Generally no. Federal rules for controlled substances describe a faxed prescription as one transmitted by the practitioner or the practitioner's agent, and mail-order pharmacies such as Express Scripts say faxes are accepted only from a doctor's office. Ask your prescriber to send the prescription electronically or by fax, or take the paper prescription to the pharmacy.

Can a doctor fax a Schedule II prescription?

Only in limited cases. A Schedule II prescription may be faxed to a pharmacy before dispensing, but the original signed prescription must be presented before the drug is dispensed. The fax itself can serve as the original only for certain compounded infusion prescriptions, residents of long-term care facilities, and hospice patients.

Can Schedule III, IV, and V prescriptions be faxed?

Under federal rules, yes. A pharmacist may dispense a Schedule III, IV, or V prescription drug pursuant to a fax of a signed paper prescription transmitted by the practitioner or the practitioner's agent. State law and e-prescribing mandates can be stricter.

What is the CVS or Walgreens fax number?

There is no single national fax number for retail prescriptions. Each pharmacy location has its own line, and prescribers get it from the store. For CVS Caremark mail order, prescribers can use the FastStart new prescription fax form (1-800-378-0323) for non-controlled maintenance drugs.

How do I move a prescription to a different pharmacy?

Ask the new pharmacy to transfer it. CVS, for example, offers an online transfer and says you mainly need your prescription label. Some controlled substance prescriptions can only be transferred once.

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