no. 01 SIMs we recommend

SIMs that fit a child's first phone.

Short answer. For a first phone with a whitelist of allowed numbers, ParentShield at £9 a month on EE. For the cheapest sensible SIM with no special features, Smarty at £6 on Three. For the bottom of the price ladder, Lebara at £4 on Vodafone. The reasoning, the trade-offs and where to buy each, below.

Four UK SIMs, ranked. ParentShield is Knock's first pick for a child's first basic phone, because the whitelist works as advertised. The others are cheaper and fine, with the trade-offs each one carries.

Last updated: 22 May 2026
SIMs in this list: 4
Affiliate links?: Yes, on the buy buttons. How we choose.

ParentShield

From £9 a month

The only UK SIM built specifically for a child's phone. Whitelist incoming and outgoing numbers. See call and text logs. Set quiet hours. The most on-brand SIM for the audience.

Our verdict. ParentShield is the SIM we put alongside a child's first basic phone. The whitelist plus the quiet-hours feature is genuinely useful. Worth the £9 a month for the peace of mind.

Data: From 250 MB to 5 GB
Minutes: From 100 to unlimited
Texts: Unlimited on most tariffs
Parent controls: Whitelist numbers, set quiet hours, see all call and text logs
Contract: Rolling monthly, no minimum
Network: EE

Where to buy

ParentShield direct

Smarty (Three)

Smarty

From £6 a month

The cheapest sensible SIM on a quality UK network. No frills, no parental controls, no contract.

Our verdict. Smarty does the job at the price. On the Nokia 3210 or 235, the network does the heavy lifting, not the SIM. Smarty is what we put on a second phone in our own house.

Data: From 2 GB to unlimited
Minutes: Unlimited
Texts: Unlimited
Parent controls: None
Contract: Rolling monthly
Network: Three

Where to buy

Smarty direct

Lebara

From £4 a month

The cheapest mainstream SIM on Vodafone's network. Strong on data, weaker on parental features.

Our verdict. Lebara is fine. If price is the deciding factor, this is the SIM.

Data: From 1 GB to unlimited
Minutes: From 100 to unlimited
Texts: Unlimited
Parent controls: None
Contract: Rolling monthly
Network: Vodafone

Where to buy

Lebara direct

giffgaff

From £6 a month

Owned by O2. Long-running, ethical-by-positioning, and the one a lot of older readers know. We list it for completeness.

Our verdict. Honestly, Smarty does the same job for about the same money. We list giffgaff because plenty of readers ask. The affiliate rate is also low (about £2 a SIM via their public scheme), which we mention for transparency, not as a reason to avoid it.

Data: From 2 GB to unlimited
Minutes: Unlimited on most goodybags
Texts: Unlimited
Parent controls: None
Contract: Monthly "goodybags", cancel anytime
Network: O2

Where to buy

giffgaff direct

no. 02 How to pick

How to pick

If your child is eight to eleven and this is their first phone, take ParentShield. The whitelist saves you the "who is this calling on a number we don't recognise" worry from week one. £9 a month, no contract.

If your child is older, or already on a basic phone and you're looking to cut the cost, Smarty or Lebara are fine. The network does the heavy lifting at that point.

Every SIM buy button on this page is a plain direct link to the provider. Knock earns no commission on SIM sales. See the disclosure page for the full picture.

no. 03 Before you pick a SIM

Questions UK parents ask, before they pick a SIM

What is the best SIM for a child in the UK?

ParentShield, £9 per month on the EE network. It is the only UK SIM built specifically for a child's phone, with a whitelist of allowed numbers, no contract, and a call log that goes to a parent's email. For families happy with no whitelist, Smarty at £6 per month is the cheapest sensible no-frills SIM.

What is the cheapest SIM-only plan for a child in the UK?

Lebara at £4 per month on the Vodafone network. Calls, texts, a few gigabytes of data. No whitelist features. Works in any unlocked basic phone or smartphone. For most families the better answer is Smarty at £6 because the data ceiling is higher and the network coverage is more consistent across UK rural areas.

Do I need a SIM with parental controls for a basic phone?

Probably not. A Nokia 3210 runs no apps and has no browser, so the SIM does not need to filter anything at the network level. The case for ParentShield is the whitelist of numbers, not content filtering. If the phone is a smartphone, the controls belong on the phone (Apple Screen Time, Pinwheel) not on the SIM.

Will a UK SIM work in an imported phone like the Light Phone III?

Yes. The Light Phone III is unlocked and supports UK 4G bands. Any of the four SIMs above (ParentShield, Smarty, Lebara, giffgaff) will work. The Light Phone uses an eSIM, so confirm the eSIM option at sign-up.

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