Can I use my personal checking account for LLC transactions?

It's a problem for liability. If your LLC is sued, the other side can argue you never treated the company as separate. That's the whole point of the LLC.

How long is 'eventually'? If it's a couple weeks you're probably fine, but if it drags on for months you're asking for trouble. I'd open the account this week.

Probably a few weeks. I was waiting on the EIN letter but it already came, so I don't really have an excuse.

Not a lawyer, but mixing funds is one of the easiest ways to lose the liability shield. Commingling is the term they use. Keep every receipt if you've already mixed things.

Also your bank might close the account if they figure out you're running a business through a personal account. Most deposit agreements prohibit it.

I did this for about six months with my first LLC and it never came back to bite me, but that was luck. I wouldn't do it again. The bookkeeping alone was awful.

mossyrock makes a good point. Some banks are stricter than others. The bigger issue is proving which transactions were business when tax season comes.

Yeah the tax part is what worries me most. I have maybe five or six deposits. I can still sort them out.

Five or six is manageable. Do it now before it's fifty. Open the account, move the remaining business money over, and document thhe deposits you already took.

One thing nobody mentioned: some states care more about this than others if you're ever in court. Where are you located?

Ohio.

I'd still treat it as urgent rather than wait. The cost of opening a business checking account is usually zero or close to it.

Honestly the waiting is the risk, not the few deposits. Get it done this week and you'll forget this ever happened.