regular timer vs. thermostat

Currently I am using a regular timer for my heat pads and just have them on at night for eight hours. I was wondering if this is more cost effective in the long run regarding electricity usage than using thermostats and have the heat pads regulated 24/7. I don't live in a place that snows in the winter.

For what it's worth I think using a heat pad on a timer and only giving your reptiles heat for part of the day is not going to be good for their health and could cause some serious issues. Do you currently have a proper digital thermometer to make sure they are being kept at steady and correct temperatures? Having their temps vary far outside of the correct ranges day and night is definitely not a good idea. And it is also known that even reptile heat pads should be regulated with at least a dimmer as they can very easily reach temperatures high enough to burn even when some distance is left between the pad and the cage.

So my recommendation is to either get a dimmer or a thermostat. A timer is basically useless for anything other than lighting(which is what I use it for) in this situation as a steady temperature range should be provided at all times. With a dimmer it will keep power going to the heat pad at all times, just at a lesser amount to keep the temps where they should be, but will have to be manually adjusted, where as a thermostat can turn the heat pads on and off to keep the temps where they should be. So even with a dimmer, if temps in your house change, either lower or spike dramatically, you're pretty much screwed. And thermostats really aren't all that expensive so I'd say well worth the money in the long run.