Do I have to issue a 1099 to a foreign company that is providing service to my US based LLC (sole-proprietorship)? I am paying more than $600/month.

[ToddL]

Unless the recipient is subject to reporting 1099 income to the U.S. (non-exempt), you do not need to report payments to them on a Form 1099-MISC. 

They are considered Exempt recipients. An exempt recipient is any payee that is exempt from the Form 1099 reporting requirements.

If the foreign recipient is non-exempt (i.e. subject to Form 1099 reporting requirements), the IRS suggests that you request the recipient complete the appropriate Form W-8. 

(Payments to foreign persons. See the Instructions for Form 1042-S, relating to U.S. source income of foreign persons, for reporting requirements relating to payments to foreign persons, at https://www.irs.gov/pub/irs-pdf/i1042s.pdf)