Necesito una tarjeta SIM.

When to use

This phrase is essential when you need to buy a new SIM card for your phone, usually at a mobile carrier's store or a shop that sells phone accessories.

How it works

This is a simple sentence structure using the verb 'necesitar' (to need) in the first-person singular present indicative 'necesito' (I need), followed by the direct object 'una tarjeta SIM'.

• necesito: first-person singular present indicative of 'necesitar' (I need).
• una tarjeta SIM: 'a SIM card'. 'Tarjeta' is feminine, hence 'una'.

Register and formality

This statement is direct and functional. It's suitable for a transactional context like a store. Adding 'por favor' (please) would increase politeness.

Notes

Phone-store starter phrase. Neutral everyday wording.