Last updated: August 2026

Both give you connectivity without financing a handset. The difference is commitment: SIM-only is a credit agreement, prepaid is not.

Direct comparison

SIM-only Prepaid
Cost per gigabyte Lower Higher
Credit check Yes, at a low threshold None
Commitment Month-to-month or fixed term None
Can affect credit record Yes, if payments are missed No
Overspending Out-of-bundle charges possible Impossible — you pay in advance

When prepaid is the better choice

When SIM-only wins

Steady income and consistent usage. The per-gigabyte saving is real, and month-to-month options mean the commitment can be minimal while still getting contract rates.

See month to month SIM only deals and SIM only deals.

The honest summary

Prepaid costs more per gigabyte and buys something a contract cannot: the impossibility of getting into trouble with it. For anyone whose circumstances are uncertain, that is worth the premium.

See prepaid vs contract, SIM only vs phone contract and no credit check phone options.

Frequently asked questions

Which is cheaper?

SIM-only per gigabyte. Prepaid may cost less overall if it stops you overspending.

Does SIM-only need a credit check?

Yes, at a lower threshold than a handset contract. Prepaid needs none.

Can prepaid affect my credit record?

No. There is no credit agreement.

Can I switch between them?

Yes, and you can keep your number either way.

More comparisons

Pricing and terms are set by each provider and change regularly.