Now probably would not be a good time to spread that around but in a few weeks, as the plants are entering dormancy could be. That would be better then putitng the bag in the basement where it may get forgotten for years.
Compost could be spread now, but not a fertilizer that may bew fairly soluble and readily available.

prairiemoon, you didn't say what brand you bought, but I use Milorganite and it stores beautifully. Early spring probably your best bet. You're right to be cautious now.

Thanks, I think I bought a couple of different kinds of Espoma, I wonder if that is soluble or more long acting?

The Espoma "-tone" products have some fast-acting nitrogen and the rest are meals that require a warmer soil to decompose. There is no need to apply now. I have bags of Espoma Rose-tone in my garage from two years ago that I haven't used yet. If needed, store in a plastic bin with a tight lid, it will be fine to use next year.

Thanks Diane, I forget which ones I have, Rosetone might be one of them. I thought I read somewhere over the summer that you shouldn't store fertilizer in the garage over the winter because if it freezes it effects it in a way that makes it less effective? So I was going to put mine in the basement over the winter. Have you heard anything about that?

If the fertilizer is a liquid freezing might have an adverse affect on it, but if the stuff is dry freezing will have no affect at all on it.

great, thanks... :-)