Neither, they are perennials. Annuals are plants that germinate, flower, set seed and die all in one season (one year), biennials do the same thing but over two seasons (or two years.)

Your Crocosmia might be sufferring from a lack of food and/or over-crowding perhaps - if the clump is very dense and has lots of leafy foliage but few or no flowers then it's worth dividing them and replanting the corms with some fresh garden compost etc. That will encourange vigorous re-growth and setting of flower buds. Alternatively they might be positioned in too much shade - although they can tolerate quite a lot of shade it does impare the flowering.