If my total tax last year was 4.7k, does the safe harbor rule mean I only need to pay 110% of that as estimated payments and I can pay the rest when I file for taxes?

[SNKRdoc]

This year my income will be significantly more and will be all 1099. I've never had to make estimated payments before since I've always had a W2 job. Last year my total tax was 4.7k before any refunds. So my question is, even if my 1099 income will be over 400k this year, do I only have to pay 110% of 4.7k this year for my quarterly tax payments?

[ee-ea]

You are right.   Remember the state.  Here is the confirmation:

https://turbotax.intuit.com/tax-tips/small-business-taxes/estimated-taxes-how-to-determine-what-to-p...

[Mike9241]

110% if your 2020 adjusted gross income is more than $150K otherwise it's 100%