House Sparrow (Passer domesticus) eggs are useful in artificial nest experiments because they are approximately the same size and shell thickness as those of many forest passerines. House Sparrow eggs can be readily collected in quantity by providing nest boxes in active livestock barns. We collected over 1200 eggs in three years (320–567 per year) from a colony of about 24 breeding pairs by providing 60 nest boxes. Eggs dry-refrigerated at 8–9°C lost mass after 2 weeks, whereas eggs submerged in sodium silicate solution at 8–9°C remained fresh for 2 months until deployment. Eggs stored in sodium silicate solution should be rinsed with clean water before use.