What determines your water bill depends on the amount of water that you have used. Most municipalities measure water by CCFs. One CCF is equal to 100 cubic feet of water which is 780 gallons. The amount of total cubic feet consumed is calculated by subtracting your past meter reading from your current meter reading.
If you only have town water you will only be billed the water rate that is used, however if you are on town sewer you will proablaly be charged a water rate and a sewer rate.
In some municipalities you also may be charged a service fee and a fire protection charge. These charges should be itemized on your bill.
There are some accounts there are tagged as “non-metered” accounts which are charged a flat rate that does not fluctuate with changes in usage and is based on factors such as building size, lot size and number of plumbing fixtures. If you have this type of an account it should be shown on your billing statement.