Hey, that's a great question! Keeping your outdoor trash bin secure is super important to prevent messes from animals, unauthorized use, or even the bin itself blowing open in the wind. From my experience, there isn't one single "most secure" lock that fits every situation, but a combination of a few things usually works best.
First, look for a bin that has integrated, heavy-duty latching points. These are often sturdy metal loops built into the bin's design. The real key is the lock you use with them. For maximum security, a solid, weatherproof padlock is your best bet. Think about a shrouded shackle padlock, which makes it very difficult for bolt cutters to get a clean cut. Combination padlocks are also fantastic because you don't have to worry about losing a key.
Another excellent option is a bin that comes with a built-in, lockable bar or latch. This mechanism physically bars the lid from being lifted and is often more convenient than a separate padlock. For deterring clever animals like raccoons, sometimes a simple but robust carabiner clip or a bungee cord with a hook can be surprisingly effective, though not as secure against human tampering.
Ultimately, the most secure setup is a layered approach: a bin with strong built-in latching points combined with a high-quality, weather-resistant padlock. This will effectively keep pests out and ensure your bin stays closed and tidy, no matter the weather. Hope this helps you find the perfect solution for your home