The plan usually costs £26 per month – which is the same price if bought directly from Vodafone. £276 cashback from Mobiles however, drops the monthly rate below £15. Just remember to claim. The rate also beats Three’s market-leading unlimited SIM-O offer, which costs £11 for six months and £22 for the rest of the 24-month term. This amounts to £462 by the end of the term, whereas, Mobile’s plan amounts to £348. See all Vodafone SIM-only plans from Mobiles.  You might also like: Best unlimited data deals in the UK Somrata researches and writes about the best tech deals to help readers make smart, informed buying decisions. She’s an expert on accessories and also reviews laptops, phones, audio and other devices.