Box12TTCode TT, worked out one workweek at a time.
Starting with 2026 Forms W-2, box 12 code TT has to show only the overtime premium the FLSA required. Upload a weekly payroll CSV and Box12TT does that math for every employee, shows its work, and marks the weeks your payroll got wrong.
Free for up to 3 employees. Your file is calculated in the browser and never uploaded.
o
d
e TT 1,284.50
- Workweek ending Mar 7, 202645.00 h
- Straight time for all 45 h, plus a $50 production bonus$950.00
- Regular rate, $950 ÷ 45 h$21.11
- Half-time × 5 h over 40$52.78
- Sum of 31 workweeks with overtime$1,284.50
The register shows what you paid. Box 12 asks what the FLSA required.
Payroll software adds up overtime earnings. Code TT is a different number: only the half of time-and-a-half, figured on each workweek's regular rate, and only to the extent you paid it. Many QuickBooks Desktop users have been entering it by hand all year, and the IRS penalty applies per incorrect W-2.
Box12TT recomputes every workweek from hours and earnings, then tells you which differences are expected and which ones need a second look.
- Time-and-a-half overtimeone third of the OT line
- Double timeone quarter of the line
- Daily overtime with 40 or fewer weekly hoursnot code TT
- Overtime paid on holiday or PTO hoursnot code TT
- Bonuses and shift differentialsraise the regular rate
- Two pay rates in one workweekweighted-average rate
- Tipped employeestip credit and minimum-wage floor
- Salaried nonexempt, fixed or fluctuatingboth methods
- Quarterly bonus true-ups and December weeks paid in Januaryreported in the year paid
How it works
Export weekly earnings
One row per employee per workweek: hours worked, straight-time pay, overtime pay. Our QuickBooks Desktop guide shows which report to use.
Drop the CSV in
Box12TT reads it in your browser, computes each regular rate and required premium, and adds bonus true-ups from an optional second file.
Enter box 12 and keep the trail
Download the code TT amount per employee for W-2 entry, plus a workweek audit trail to file with your year-end papers.
Pricing
One price for the whole W-2 season. No subscription, no per-client fees.
Free
For checking a small employer or trying the method.
- Up to 3 employees per file
- Full workweek math on screen
- Sample data to test with
2026 W-2 Season Pass
One-time payment, valid through April 30, 2027.
- Unlimited employees and client companies
- Box 12 amounts as CSV for W-2 entry
- Workweek detail CSV and printable audit trail
- Refund within 14 days if it doesn't fit your data
Questions
What goes in W-2 box 12 code TT?
Only the overtime premium FLSA section 7 required: half the regular rate for each hour worked over 40 in a workweek, to the extent you paid it. Read the code TT guide for worked examples.
We use Gusto, ADP or Paychex. Do we need this?
Full-service payroll providers compute code TT for their own customers. Box12TT is most useful when payroll runs in QuickBooks Desktop or another in-house system, when you inherited a client mid-year, or when you want to check a provider's figure with the same weekly data.
Is my payroll data uploaded anywhere?
No. The calculator is plain JavaScript that runs in your browser tab. The only network request it makes is checking a license key you paste in.
What can't it handle yet?
Public-sector comp time, salaried nonexempt employees whose salary covers more than 40 hours, and retroactive raises other than bonuses. Those weeks need a manual calculation; the tool flags the cases it can detect.
Is this tax advice?
No. Box12TT is a calculation aid. It applies the FLSA regular-rate method described in IRS guidance for 2026 Forms W-2. Review flagged weeks and confirm positions with a tax professional.
What if it doesn't work with my data?
Reply to your receipt within 14 days and you get a full refund.