RxBIN, RxPCN and RxGroup, what each one means.

The four numbers a pharmacy bills with

When a pharmacy fills a prescription it sends an electronic claim, and the claim has to reach the right payer before anything else can happen. The National Council for Prescription Drug Programs (NCPDP) and CMS call the routing and identification data the "4Rx" data set: RxBIN, RxPCN, RxGRP and RxID. In the Medicare Part D documents the four are described as the Bank Identification Number, the Processor Control Number, the Group ID and the cardholder ID defined by the plan.

Think of it as an address. The BIN says which processor network the claim goes to, the PCN narrows it to a processing arrangement, the group says which drug benefit you belong to, and the ID says which person. A claim missing or mistyping any of these usually rejects at the pharmacy counter, which is why people go looking for what the abbreviations mean.

RxBIN: six digits, all of them matter

NCPDP's overview of the Medicare Part D coordination-of-benefits process says the BIN is "a numeric field where all six digits are required" and is used for routing within the pharmacy industry. A BIN can be obtained through NCPDP or through ANSI. When it is used in the Medicare Part D environment it is simply called the RxBIN. Because all six digits are significant, a dropped leading zero or a stray extra digit is a real error rather than a formatting quirk. The checker above flags any BIN that is not exactly six digits, and any that contains letters, which usually means a PCN or group number was pasted into the wrong box.

RxPCN: ten characters at most, and sometimes blank

The same NCPDP document describes the PCN as "a 10-character value (all 10 characters are not required)" that is typically assigned by the plan sponsor's processor and "optionally used for routing." So a PCN is up to 10 characters, it is often short, and some cards print none. The sources do not fix which characters it may contain, so the tool checks length only. In Medicare Part D the unique RxBIN and RxPCN pairing also helps the Part D transaction facilitator recognise which payments count toward true out-of-pocket costs, which is why a supplemental payer is told to obtain its own unique combination.

RxGroup, and why it is not your medical group number

RxGRP is the Group ID. It identifies the specific drug benefit you are enrolled in, and neither the sources we read nor the card layout set a fixed length or character set, so the tool never rejects a group number. It can differ from the group number used for medical claims, so read the line labelled RxGRP rather than assuming. When a pharmacy asks for "the group" and you read the wrong one off the card, the claim rejects. CMS's model Part D member card shows the fields in a fixed order: RxBin, an issuer number (80840 on the model), RxPCN, RxGRP and the cardholder ID, with the plan sponsor name above them.

Worked example with made-up numbers

Suppose a card reads RxBIN 123456, RxPCN ABC1, RxGRP DEMO01. These values are invented for illustration and belong to no plan. The BIN has six digits, so it passes. The PCN has four characters, which is within the 10-character limit. The group has no format rule. Now suppose someone types the BIN as 12345: that is five digits, so the checker flags it, and the likely cause is a missing digit. If they type the BIN as ABC1, it is non-numeric and probably the PCN in the wrong field.

Pasting the member ID in the BIN field is another common slip, and the length check catches most of those too.

Common mistakes and what this does not cover

• Reading the medical group number, the plan name or the employer name instead of the RxGRP line.
• Using the card for the medical plan when the pharmacy benefit has its own card.
• Entering a PCN that runs together with the group, which makes it longer than 10 characters.
• Assuming a blank PCN is an error. The sources describe it as optional.

This page does not publish a list of BIN numbers and it cannot tell you which benefit manager a BIN belongs to. We did not find permission terms for republishing a BIN directory, so none is included. It will not look up a member, and it does not accept or need personal information: a member ID, a name or a date of birth does not belong in any of the three boxes. For a rejected claim, the support number on the back of the card is the right route, because only the plan knows whether your enrollment is active.

Sources

• NCPDP: Overview of the Medicare Part D Prescription Drug Coordination of Benefits Process (August 2026) — 4Rx data definitions; BIN six digits; PCN up to 10 characters
• CMS: Draft Model Part D Member Identification Card — field order RxBin, Issuer, RxPCN, RxGRP, ID
• CMS: Medicare Prescription Drug Benefit Manual, Chapter 14 — 4Rx data defined as RxBIN, PCN, RxGRP and cardholder ID

Every figure and rule above was retrieved from these pages in October 2026. Agencies revise forms, codes and percentages, so confirm anything that affects a claim, a filing or a deadline against the current official page.

Frequently asked questions

What does RxBIN mean?

RxBIN is the Bank Identification Number used to route a pharmacy claim to the correct processor. NCPDP describes it as a six-digit numeric field where all six digits are required. It can be obtained through NCPDP or ANSI, and the Medicare Part D documents call it the RxBIN.

What does RxPCN mean?

RxPCN is the Processor Control Number. NCPDP describes it as a value of up to 10 characters, typically assigned by the plan sponsor's processor and optionally used for routing. Some cards leave it blank.

What is RxGroup (RxGRP) on my insurance card?

RxGRP is the Group ID, the number that identifies your specific prescription drug benefit. It is one of the four data elements, with RxBIN, RxPCN and the cardholder ID, that CMS and NCPDP use to process a pharmacy claim.

Is my RxGroup the same as my medical group number?

Not necessarily. The RxGRP on your pharmacy benefit card can differ from the group number used for medical claims, so give the pharmacy the number on the line labelled RxGRP.

Does a PCN have to be filled in?

No. NCPDP says all 10 characters are not required and the PCN is optionally used for routing, so a card with no PCN is not necessarily wrong. If the pharmacy asks for it and your card shows one, give it exactly as printed.

What is the fourth number, RxID?

RxID is the cardholder ID defined by the plan, the member-specific number. It is the only one of the four that identifies you personally, which is why this page never asks for it.

Why does the pharmacy need all of these?

The claim has to reach the right payer and then the right benefit and member. The BIN and PCN route it, the group selects the benefit and the ID selects the member. CMS says the billing information on a Part D sponsor's card must be used to submit claims so enrollees get the negotiated prices.

Can I find out which company a BIN belongs to here?

No. This page explains the fields and checks their shape. It does not publish a BIN directory. The customer service number on the back of your card is the reliable way to confirm who processes your drug benefit.