Why would I need to make estimated quarterly payments of $3416 for 2019 if I only underpaid by $893 for tax year 2018? This is what turbo tax suggested!!!

[Critter]

Your final balance due this year is not the way estimates are calculated ... and you had the chance to enter in some info for 2019 in the estimated payment section that would effect the estimated payment amounts ...

Do I need to make estimated tax payments to the IRS?

https://ttlc.intuit.com/replies/3301891

Why did 1040-ES estimated tax vouchers print out? Do I need them?

https://ttlc.intuit.com/replies/3301872

How does TurboTax calculate my estimated tax payments?

https://ttlc.intuit.com/replies/3301730

[pk]

A point to note is that the 1040-ES quarterly shows 25% of your total  ( expected ) tax liability --  it disregards what would be automatically withheld  on your W-2 for the coming year.  Also this is only a suggestion and not compulsory.