UK number ranges affect what callers pay and what a business should disclose. 01 and 02 are geographic; 03 is national and charged at no more than geographic rates; 0800 and 0808 are free to callers from UK fixed and mobile phones.
084 and 087 calls use an access charge set by the caller's provider plus a service charge set by the service provider. They are not normally included in inclusive minutes. Make the service charge clear wherever the number is advertised.
Rules can change, so use current Ofcom guidance and ask your provider to confirm the tariff and disclosure wording for your number.
Check Ofcom's current phone-number guidance ↗. You can also compare UK number types or browse compliant options.