All our fabrics are machine washable and can be cleaned on a bleach solution wash without strinkage or fading. Naturally, if stains are left on the covers for an extended period of time, it is going to become increasingly more difficult to remove the marks. Simply follow this chart on cleaning your furniture covers: https://global.sunbrella.com/en-us/how-to-clean and aim to regularly wash to remove build up of dirt, sweat and pollution.