I got a single DUI on my record and blew a .08 back in 2003. I live in California and it's been past 10 years so the offense is off my driving record. However, will this affect me in any way as I pursue my goal in becoming a commercial pilot?

Do you have a FAA medical certificate? If not, google FAA form 8500 and look at question 18v.

Yeah, I looked it up and I would have to check that box. Would that affect me in any way given that it was my only offense and now off my driving record?

Yes, it will almost certainly make getting an FAA medical hard. Is it still possible? Yes, but you'll probably have to spend quite a bit of time convincing the FAA's AMEs.

Good news...

1) Ten+ years ago.
2) One-time event.
3) BAC barely at the legal limit.

Odds are that the AME will be able to issue you a 1C on the spot, although the FAA might possibly follow up with some additional requests for information.

I would talk to an aviation medicine consulting company BEFORE you talk to the FAA or an AME, just to get all of your ducks in a row. You will want to have all the paperwork, including case disposition and most especially BAC.

As for airlines.... regionals won't care (some actually prefer DUI's because they know you'll stick around longer). For majors it will delay your call but by the time you get there the impact should be minimal for the reasons I mentioned. But you need to keep a clean record in all things because you already have one strike...

Here is a pretty good link.

Do a google search for 'FAA guidance to AME' it should be one of the first hits.

Once there, the link you need to be looking for is Substances / Dependence / Abuse

(This can be a tricky subject for some guys ... I'm not suggesting that this may be an issue. Rather, this is just where the FAA has tucked away the DUI/DWI Alcohol Incidents Disposition Table).

Thresholds the AME will be looking for: 5 or more years ago, single incident, BAC less than 0.15

Sounds like you can check all of these boxes, but there is still discretion on the AME's part via the exam and interview.

I would bring any/all paperwork that you have, particularly the police report with the BAC. If BAC is unavailable/unknown ... there are different procedures the AME will have to follow (and that is where the 10 years in the rearview comes into play)

You may have to submit a personal statement as well — something along the lines of 'I messed up, here are the facts/dates, and I know what a big mistake this was. Here is my plan so it won't happen again.'

Good luck. The road back after one event is relatively easy with the right mindset. Two (or more) events make it incredibly tricky, perhaps unlikely, and/or prohibitively expensive to receive a medical certificate.

Now, even after all of that, all we're talking about is the medical certificate ... whether or not an employer will consider your application is another matter.

I tend to agree with Rickair7777's assessment (regionals = yes, majors = maybe, after a delay).

A respected AME said elsewhere that the audit rate for AME issued medicals with DUI hits is 100%, so the AME needs to be sure your story is solid.

In addition to all the above advice, you will also need to do the Canadian paperwork to be certified as rehabilitated. Given the timeframe, it should just be a paperwork drill, but does have to be done or you cannot enter Canada. (And most regionals fly there...)

Yes you'll have to pay a "fee" (bribe) to be "rehabilitated" so as to be deemed suitable to enter canada.

Thank you all for the help.

- The link helped a lot. I guess I'll have to take a trip down to the police station to get my files.