What mistakes make it easier to hold an LLC owner personally liable?

Biggest one I've seen: commingling funds. If you use the LLC bank account for personal expenses, or pay personal bills from it, that's a fast track to losing the shield. Keep separate accounts and don't treat the LLC like a piggy bank.

Not maintaining formalities is another. No operating agreement, no minutes, no separate records. Courts may disregard the entity if it looks like an alter ego.

So the operating agreement isn't just a formality? I was planning to use a template and not think about it much.

A template is better than nothing, but it should be tailored. If the agreement is generic and doesn't reflect how you actually run things, it won't help much. Also, failing to document major decisions can hurt.

Undercapitalization. If the LLC has no real assets or insurance and you're personally covering everything, a plaintiff might argue the LLC was a sham.

Not using the LLC name on contracts and invoices. If you sign personally or don't make it clear you're acting for the LLC, you can be on the hook.

Agree with riverstone. Also, personally guaranteeing loans or leases. That's a direct personal liability regardless of the LLC.

And don't forget mixing personal and business in communications. Using your personal email for business, or not having a separate phone line, can blur the lines. It's not a single factor but adds up.

This is helpful. I hadn't thought about the communication side. What about having a registered agent? Does that affect liability?

Registered agent is more about service of process. Not directly liability, but if you ignore legal notices because they went to an outdated agent, you could lose by default. That's a different kind of mistake.

Also, acting as the LLC without mentioning it. Like signing a contract as 'John Doe' instead of 'John Doe, Manager of XYZ LLC'. Courts may hold you personally if the other party didn't know they were dealing with an LLC.

One more: not keeping licenses and permits in the LLC's name. If you operate under your personal name for regulated activities, that can create personal exposure ngl.