Can anyone tell me how old a dog must be before you can have the correct vaccinations to obtain a passport?

Many thanks

You can have the rabies jab from 12 weeks onwards. Don't forget though that the whole process takes about 7 months to process to re-gain entry into the UK. Mine have the rabisin jab which is a vacination for 2 years . The jab is around £25 and blood work is about £50.00 + microchipping.
Hope this helps
Andrea