Bowker (MyIdentifiers)
Official US ISBN agency. Relevant if your publishing entity is US-based. UK authors should normally buy from Nielsen instead of Bowker.
Nielsen ISBN Agency (UK & Ireland)
What it is
Official ISBN agency for the UK and Ireland. Buy your own ISBNs if you want your imprint listed as publisher (rather than a platform-assigned free ISBN). Not legally mandatory to publish, but expected for bookstore/library channels.
Pricing model
Paid — Purchase via Nielsen ISBN Store; packs of ISBNs. Always confirm on the vendor site before buying; plans change.
Regions
UK
Affiliate
Affiliate link: none yet.
Honest note: IndieShelf blurbs are written from public positioning. We do not republish vendor marketing copy wholesale and we do not claim rankings we did not earn.