Check with the Humane Society or London city hall. I know that in Toronto the city has an Animal Services dept that operates spay/neuter clinics. There, the cost to spay is $89. However, the waiting list is obscenely long and because of that, I must take Sadie to her regular vet and pay approximately $250.00 instead! Also, if I were you, I'd call around for prices. In my neighborhood the price ranged from $160 (but they don't do pre-op bloodwork or send pain medication home) to $500. Note, the $500 vet didn't appreciate it when I questioned their high prices. They said "but our facility is really, really nice." My reply - "that's nice, but do you really think Sadie is going to care about getting operated on at the Taj Mahal - particularly when she's going to be knocked out?"