That's a great and very practical question! The short answer is yes, you absolutely can purchase replacement parts like lids and liners for many outdoor trash bins. It's a common need, as these parts are the first to wear out or get damaged.
First, check with the original manufacturer. This is your best bet for a perfect fit. Look for a model number or brand name on the bin itself, usually on the side or under the rim. Visit the manufacturer's website or contact their customer service directly. Companies like Rubbermaid, Simplehuman, and Toter often sell specific replacement parts for their products.
If the manufacturer doesn't have the part or the bin is generic, don't worry. Many universal or compatible lids and liners are available at major home improvement stores (like Home Depot or Lowe's), online retailers (Amazon, Walmart.com), and specialty container websites. The key here is accurate measurement. For a lid, measure the outer diameter of the bin's top opening. For a liner, measure the interior height and width (or diameter) at the top.
Before you buy a new part, consider a quick DIY fix for minor cracks in a lid using a sturdy plastic repair epoxy or heavy-duty tape as a temporary solution. However, for safety, cleanliness, and pest control, replacing a badly damaged lid or a torn liner is always the best long-term choice.
So, while it might take a little searching or measuring, replacing just the part instead of the entire bin is usually possible and can save you money and reduce waste.