For 1099 contractors & freelancers
Yes, the business-use share of your home internet bill is deductible if you work from home as a freelancer or 1099 contractor.
Schedule C, line 25 (Utilities), or as part of the home office deduction on Form 8829.
Deduct the percentage of your internet use that is for business. If the connection serves a household, a business share well under 100% is more realistic and easier to defend.
If you take the regular-method home office deduction, you can instead include internet with your other home expenses on Form 8829. Don’t deduct it in both places.
Bills and how you estimated the business share.
In Smart Deductions, this is suggested as Phone & Internet (Schedule C line 25). You confirm it before it counts.
Sources
General information, not tax advice. For your specific situation, check with a CPA or Enrolled Agent.