Is it crushed? or whole? If crushed it is less likely to still be good. But, if you are ready to use it, open it and taste a bit, if it doesn't taste stale it should be good.
I always have quite a bit of un-crushed malts in my inventory that are a year old. If I suspect they have lost some of their freshness I will add a little more than called for. I have not had any problems with this method so far. - 5 years.