I would just refrigerate and use the jam. Do you have any 4 oz. jars? I always have one ready whenever I make jam. Some times I need it and sometimes I don't.

Its fine, just refrigerate as mentioned. I always end up with a half filled jar at the end of a canning session. Usually, because I make big batches of jam, I fill pint jars instead of the 8 ounce ones. That way, if I have half pint, it fits into an 8 ounce. Same as above, fitting in a smaller 4 ounce jar too A vacuum will still be present, but because of the extra head space its wise to keep it in the fridge.

You need to keep it in the fridge. Never process a half full jar.
If too much headspace is allowed, the food at the top is likely to discolor. Also, the jar may not seal properly because there will not be enough processing time to drive all the air out of the jar.

Ah, OK. I thought there might be a problem, but just wanted some back up. ;) Thank you all for your advice.

Got to get me some of those little jars too.

-Jenny

If the last bit doesn't evenly fill a small jar, I just put it in a tiny bowl and use it over the next few days. It's always nice to have some uncanned product to see how the texture and taste came out.

Melissa