Gather all your equipment. The jars, rings, lids, your canning pot, etc.
Add your canning lids and rings into a large pot and add water to cover them. Heat the water over medium for a few minutes, but don't boil it. Then turn the heat off.
Wash and scrub your peaches.
Peel your peaches, and cut them in half, and remove the pit.
Cut your peaches into additional slices if desired. You can add them to your jars in halves, quarters, or slices. Fill the jar up to 1 inch from the top.
Carefully pour (or ladle) the simple syrup into the jars enough to cover the peaches completely. Make sure to leave at least 1/2 an inch of space at the top.
Wipe the jar mouth and sides clean of any excess syrup or peach juice.
Remove 1 canning lid and ring from the hot water and place them on the jar, and twist to close.
Repeat with any additional peaches and jars.
Add the peach jars to your large canning pot and cover them completely with water. Having it go at least 1 inch above the jars. Cover the pot with a lid.
Heat the pot over medium high, and bring the water to a rolling boil. Let the water boil for 15 minutes (for pints) or 25 minutes (for quarts). Make sure to add more water if the level goes too low.
Carefully remove the jars from the water and set them on a towel to cool.
As the jars cool, the lids should seal. You might even be able to hear them pop. (Test the lids with a finger, the middle should not pop down, they should be tight)**
Once all the jars are sealed, label them with the date (and peaches, if you might forget ;) ) Store them in a cool, dry place for up to 18 months.