While it’s not an exact science, it’s recommended that you change your mattress every 7 to 10 years. By this point, your mattress is probably not giving you the support or comfort that you need to get a good night’s sleep. There’s a good chance that an army of dust mites and bacteria have crept their way into your mattress over this period of time too.
It’s also possible that you’ll need a new mattress before the 7-year mark is up. If you’re not getting quality sleep, it’s not worth waiting it out.