Did you really tell nobody at your work that you were in a different country? Your boss? HR? If so, why?

They could also be very interested in why you were working in a country but only on a tourist visa. That may set some alarm bells off regarding honesty.

@PeteCon That was my first thought as well. We don't know what country it was, but generally you're not allowed to work while on a tourist visa. I'd say that's probably a bigger problem then what country it was.

@DJClayworth I mentioned in my post as well: I didn't think my private life was relevant, I thought it would raise eyebrows, and I didn't think the info was relevant to my job. Other employees traveled (e.g. for leisure or to visit relatives aboard) while working all the time. That's more or less what I was doing.

@Dnomyar96 I was working for a US company. It was a tourist visa because I was indeed a tourist. I wasn't employed by a foreign company.

@gregarious As far as I understand it (IANAL), that doesn't really matter. You're not allowed to work period. It doesn't matter who it's for.

@gregarious Working abroad (which is different from merely traveling abroad) raises issues for even a normal non-clearance company, especially when that country is not a friendly one. I think the company might have wanted to know. In any case, your desire to keep your private life private may be about to come back and bite you.

As someone with a security clearance, you are expected to be aware that your travel is relevant to that clearance. You are also expected to be aware that there is no "innocuous information". Your clearance makes your private life relevant. If you were abroad more than 6 months, you may be committing tax fraud on top of any other dishonesty regarding your working situation.

"What should I say/do going forward?" - Working while on a tourist visa was probably a mistake. You should be honest and forthright going forward. You may well be denied a security clearance, but dishonesty at this point would be a big mistake.

It's not certain that working remotely on a tourist visa is illegal. It will depend on the country and the circumstances. In any case it's only slightly relevant to the question. Also can you tell us what kind of clearance you will need?

"I just did my work like normal, and whenever my location/timezone came up, I'd mention my official US address." - as a reflection, this detail is the root of the problem. In the future, be upfront and truthful with aspects like these that can have undesired consequences.

How much is "extended periods"? @gregarious

How long did you work in that foreign country ? Was it a few weeks, a few months , 1 year or longer than that ?

Some comments here are claiming working with a tourist visa is unwise or illegal. It is going to come down to exactly which specific visa and what specific country. Different countries have different rules. Some countries certainly allow you to work remotely with a tourist visa. The general concern with working with a tourist visa is that you are "stealing" jobs from locals. If you are working remotely, that is not the case. As I said, it will come down to the specific visa and the specific country you travelled to.

“What should I say/do going forward?” - Be 100% truthful on the submission of your SF-86. You will be required to provide information about you that covers between 5-10 years depending on the level of security clearance you require. Part of that process is listing individuals who knew you at those locations. You will be required to provide your passport number, the federal government has access to those records, so being truthful is your only hope of passing the type of background required for a security clearance issued by the US government

What does security clearance mean? Is it a company-specific or a well-defined government clearance (with a given level?)

I'm not sure how you can say that the general concern is "stealing jobs". Living in a country and using the infrastructure without paying income tax to support it is also a big concern. The OPs offhanded attitude that a tourist visa is fine because they are working for a foreign company makes me think they didn't bother to figure out whether for this specific country and this specific type of visa they are allowed to the specific type of work they are.

@pytago It is a status conditionally granted by the US federal government. There are many levels of security clearances. The US federal government requires that workers who will have certain jobs must be checked and verified to determine the levels of risk those workers pose to the security of classified (secret) information that they may learn as part of the job they are being considered for.

@pytago For a worker to hold such a job, they must first submit extensive paperwork detailing certain personal information about their life. That information is then verified by investigators. Depending on the clearance level, the investigators may conduct more detailed investigations, such as interviewing friends, family, and other acquaintances of the applicant.

At higher clearance levels, the applicant themselves are also interviewed, sometimes with a polygraph machine ("lie detector"). If the information provided by the applicant or the investigation or interviews reveals information that suggests the applicant cannot be trusted with government secrets, the application will be denied. The applicant will be prohibited from working jobs that require a security clearance.

If the application is granted, because the applicant is deemed trustworthy, then the applicant can work in places and with information that requires a security clearance. The process is repeated at periodic intervals to confirm that the clearance holder is still trustworthy.

Since not everyone can get a clearance, and higher level clearances are hard to get, there is continued demand for cleared workers ("cleared" means they have been granted a security clearance by the government). Because of the demand, salaries for cleared jobs are generally higher, with increased compensation at higher levels of clearance. Also recruitment for cleared workers can be aggressive.

@Dnomyar96 you're not allowed to work for a local business. No one cares if you work for a remote one in your home country. Most tourists do so these days. Your understanding is incorrect.

@EricNolan if it was a concern then tourists wouldn't be allowed into any country. There's no material difference to the host country between OP playing League of Legends on their laptop for 3 months and OP writing code on the very same laptop for a company in the US.

@ToddWilcox So security clearance is indeed ambiguous without further explanation about the level. Since the discussion is now in chat and OP didn't provide the necessary information, I voted to close as company-specific. How can anyone answer the question without knowing the required clearance..

@EricNolan Since others have raised this issue as well: I did indeed research if I was allowed to do remote work on a tourist visa. As far as I know, the host countries don't care if I'm doing work for a US company; however, if I wanted to work (either in-person or remote) for a local company, then I would need a work visa. Note that this info is based on research I gathered from the internet; I didn't consult a lawyer or government official. Also, the laws may have changed since that time.

@knallfrosch @DJClayworth I added the type of clearance needed: public trust, either low or moderate (not sure which).