Paper envelopes in a plastic box in the salad compartment of the fridge.

Can't say any better than Owdboggy.

I have no spare room in my fridge but as said paper envelope in a plastic container. The paper envelope can absorb any remaining moisture.

Thanks everyone. Will get my sons spare school lunch money envelopes left over from a long time ago and recycle them!

Recycling lunch money envelopes will be a great use for them. A resealable plastic sandwich bag might be squeezed in to your fridge salad drawer more easily than a box. The idea is to keep the seeds at a low temperature to stop them drying or germinating until you want to sow them. Depending on what you are saving it might be easier to sow them immediately where you can keep an eye on them. Lots of plants self sow and germination happens when the conditions suit the plant.

Those are what we use too!

The seeds in question are hybrid and wild aquilegia seeds, foxglove, holy hock, lady in the mist, tree peony, marigold and cosmos seeds to name but a few! Thanks everyone.

The aquilegias and foxgloves regularly self seed in our garden. Both are very promiscuous so may not come true but can provide some delightful new colours.