If you feel that your water bills are higher than expected, first check the reading on your meter to ensure it was not overread. Next, you should search for any hidden leaks. To detect leaks, turn everything off carefully so water is not being used anywhere in the house. Do not turn off the commodes, but be sure they haven’t recently been flushed. Turn off your icemaker if you have one. Then check the test hand on your meter (a small red triangle slightly to the left and below the center of your meter or the long sweep hand much like the second hand on a watch or clock). If it is moving at all, then you have a leak. If your meter does not have a test hand, then you will need to write down all the readings and go back and do the same thing in about 15 minutes. If there has been a change in the readings, then you have a leak.
Toilets are notorious for hidden leaks. They can waste hundreds of gallons a day undetected. Leaks occur when the toilet is out of adjustment or when parts are worn, so it's important to check periodically.
If both your electric and water bills have increased drastically, then it is safe to assume you have a hot water leak somewhere in your home. This could be in your electric water heater or in a hot water line somewhere within or under the house.