I donate to the Scottish Milk Bank. They're so incredibly helpful.
Thank you so much for considering this--my son had donor milk in the NICU and Special Care for two weeks as I had low supply due to my health. It was so good to know he was getting EBM. The screening form for the Scottish Donor Milk Bank is here: https://www.nhsggc.scot/hospitals-services/services-a-to-z/milk-bank-scotland/
You can donate it to neonatal units, but I just donated mine though the Facebook group 'human milk 4 human babies' someone's baby was failing thrive and they came and collected it from the house.