In 2018 I got a refund of $1500. This year I owe $1600. Nothing has changed aside from making $27k more in 2019 but a $3,000 difference seems high. Any insights?

[fanfare]

the first tax bracket is 10% and climbs from there. does that help ?

[rjs]

"Nothing has changed aside from making $27k more in 2019"

Having $27,000 more income is a big change.

We can't tell anything from just the difference in income and the difference in tax. You haven't given any information about your total income, amount of tax withheld, and the type of income. If your income is mainly salary (on a W-2), what most likely happened is that you didn't have enough tax withheld from your pay. If you are in the 22% tax bracket, the tax on $27,000 would be almost $6,000, so a $3,000 difference doesn't seem so high.

To avoid owing a large amount for 2020, use the Tax Withholding Estimator on the IRS web site to figure out how to adjust your withholding.