Ironically, most supermarket own brand sun cream is the highest rated – and also the cheapest…
Agree with Huw on Aldi, but you can get some good ones from Sainsburys, ASDA and probably the rest of them too. I know for sure that ASDA’s own brand and Sainsburys is 5-star rated for UVA – ideally you’re looking for 5-star UVA and factor 50+ to provide the highest level of UVB protection. With both combined, that offers the maximum amount of protection from both harmful elements.
The indicator is on the back of the bottles – and goes to a maximum of 5 stars – interestingly, some of the main and more expensive brands – Nivea, Ambre Solaire etc. are only 3-4 star rated.
You can also get sensitive or moisturising versions depending on preference.