It depends on a few things, like what type of skin cancer and what happened.
If you have had a melanoma, you’ll need to wait five years after completing treatment. Read more about it here.
For basal cell carcinoma, squamous cell carcinoma not treated with radiation, or solar or senile keratoses, it depends on the treatment. If you’ve been treated with fluorouracil (like Efudix), you can donate seven days after completing treatment. If you had it removed, you can donate straight away — as long as there are no signs of infection, redness, swelling or sutures. If sutures are present you can still donate plasma.