Can an ISRC be reused?

Not once it has been used. A code that has been delivered to a distributor, embedded in a master or published anywhere is spent permanently, even if the release is cancelled. A number you reserved internally and never used can be returned to the pool.

Does a remix need a new ISRC?

Yes. A remix is a different recording, as is a different studio take or an edited version, for example one edited to remove profanity. Re-releasing, re-uploading or changing artwork does not.

Does a remaster need a new ISRC?

Normally no. The IFPI Handbook treats a remaster as fundamentally the same recording, so it keeps its ISRC. A new one is only appropriate where the remastering involved significant new creative input.

Does changing distributor change my ISRC?

No. A recording keeps its ISRC permanently. Changing distributor is exactly how a recording ends up carrying two codes, which is a problem to avoid rather than to fix afterwards.

Does a music video need its own ISRC?

Yes, from your video registrant code. Audio and video are numbered independently, so both can hold the same designation number in the same year without conflict.

Do I need to keep a record of allocated ISRCs?

Yes. IMI can require the complete list of codes you have assigned and where the content is deployed, within 10 days. It also has to be reported annually. A register is not optional bookkeeping.

How to Allocate ISRC Codes: Rules and Common Mistakes

Once you hold a registrant code the numbering is yours to run, and yours to corrupt. The rules that matter, and the failure nobody warns you about.

Holding your own registrant code means the numbering is yours to run. It also means it is yours to corrupt, and the mistakes are permanent.

A note on the words, because the Handbook is strict about them: a registrant code is allocated to you for future use; an individual code is assigned to a specific recording. What follows is about assignment: the part you control and the part that goes wrong.

The one rule everything else follows from

A code that has been used is spent forever.

Once a code has gone to a distributor, been embedded in a master you handed over, or appeared anywhere publicly, it belongs to that recording permanently. Not reassignable, not recyclable, not reusable if the release is scrapped.

A number you merely reserved internally and never sent anywhere is different, that can go back in the pool. Which is why it is worth tracking those two states separately: reserved and not yet used, versus issued and gone. Without that distinction you will either burn numbers you could have reclaimed, or worse, reuse one you had already sent out.

When a new code is needed, and when it is not

These are not house rules. They are set out in the IFPI ISRC Handbook, which is the authority.

New code: a new recording · a music video of the same song, from your video registrant code · a remix · a different studio take, even with the same personnel · an edited version, such as one edited to remove profanity · a cover by different artists, which is a different recording of the same work.

Same code: re-release · re-upload · new artwork · new distributor · reuse on a compilation without change · selling or licensing the recording on unchanged.

⚠️ A remaster normally keeps its ISRC. This is the one most people get backwards, including us until we checked. The Handbook treats a remaster as fundamentally the same recording; a new code is only appropriate where the remastering involved significant new creative input.

Length changes have a threshold. Where a recording is edited in a way that does not substantively affect the creative input (a speed change, a different fade-out), a new ISRC is assigned only if the length differs by 10 seconds or more. Trimming silence, ambience or applause does not need one at all.

The dividing line is whether the recording changed, not whether the release did.

The failure that catches labels out

A recording keeps its ISRC for life. A distributor’s upload flow will issue one automatically unless you supply your own.

Put those together and the failure is obvious in hindsight: move a catalogue to a new distributor, let the new one auto-assign, and recordings that already carried a code pick up a second one. Both are real, both are permanent, and there is no mechanism to merge them. Royalty and analytics reporting can then split across two identifiers for the same recording.

There is no clean repair. The discipline is preventive: always supply your own code at upload, in whichever field the distributor offers for it, on every release and every migration.

Embedding is not the same as allocating

Writing a number in your register does nothing on its own. The code has to reach the recording:

the distributor’s “use my own ISRC” field at upload, this is the one that actually matters;
and in the file’s own metadata as a backstop.

Verify after release that the platforms show the code you allocated. If they show a different one, the distributor assigned its own.

Keep the register, because you will be asked

Two obligations make this non-negotiable rather than tidy-mindedness: IMI can require your full list of allocated codes and where the content is deployed within 10 days, and the digital repertoire list is due annually.

So record, per code: the recording, the version, the state (reserved or issued), and where it went. Retro-fitting that from distributor dashboards years later is miserable, and for anything you have taken down, impossible.

Up: ISRC. Related: an ISRC is not copyright registration.

Allocating ISRCs without making a mess of your catalogue