Holder for beverages, whereby the holder includes a rigid outer holder that is provided with a mouth for inserting a flexible inner holder, whereby the holder also includes an adapter, that is designed to be provided on the mouth and which is designed to be coupled to a coupling element of such an inner holder, so that in this way an inner holder, with a coupling element that is too small to be provided on the mouth directly, can nonetheless be provided on the mouth. The outer holder and the adapter are fitted with a complementary first unit to lock their mutual position when they are coupled, whereby the locking is repeatedly reversible.