If you are Scottish or from a country from within the EU usually SAAS will pay your tuition fees. You may also be entitled to a student loan.
If you are English or from another country out with the EU you may have to pay fees.
Bòrd na Gàidhlig has a bursary scheme, for students studying to become Gaelic teachers, which may cover course fees. A small bursary may also be on offer.