Confirm the entry conditions for your own passport, residence and travel purpose with an Iranian embassy or consulate before making non-refundable bookings. Check whether you need a visa, passport validity, permitted stay, required documents and transit conditions. Advice written for British passport holders does not establish the rules for other nationalities.
If you have Iranian nationality or an Iranian father or spouse, check your position carefully: FCDO says Iran does not recognise dual nationality and may treat affected travellers as Iranian nationals. It also notes potential refusal where a passport has Israel-related stamps. Ask the responsible authority what applies to your circumstances rather than relying on a rule for someone else.
See the Iran visa information and enquiry page to check what assistance is available for your case. The link does not confirm a purchasable visa option or approval. Verify customs and medicine rules, carry copies of relevant documents and confirm any child-travel requirements. Iranian authorities decide entry, and requirements can change.