CT-1120K: Business Tax Credit Summary (2024)
Connecticut · Connecticut DRS · Used for tax years 2024
Form CT-1120K summarizes Connecticut business tax credits for the 2024 income year and calculates the credits applied to the Corporation Business Tax. It reports credit amounts claimed, carrybacks and carryforwards, credits shared with unitary affiliates, and amounts applied to o
Who files this form
Attach Form CT-1120K to Form CT-1120 or the applicable tax return whenever you claim tax credits from the current income year or have carryforward tax credit balances from a prior year.
The instructions require this attachment for corporation business, unrelated business income, air carrier, railroad companies, community antenna television system companies, utility companies, public service companies, and petroleum products gross earnings tax returns when either condition applies.
Each member included in Form CT-1120CU that claims, applies, or shares a tax credit must file a separate Form CT-1120K.
Insurance and health care taxpayers covered by the instructions use Form CT-207K instead. Personal income tax filers use Schedule CT-IT Credit.
What you'll need
Have the following available to complete the summary:
- Form CT-1120, Form CT-1120CU, or the applicable tax return. CT-1120K uses amounts from these returns and sends credit totals back to them.
- The applicable credit forms listed beside the credits you claim, such as Form CT-1120HPC for Housing Program Contribution or Form CT-1120RC for Research and Experimental Expenditures.
- Your corporation name and Connecticut Tax Registration Number. The form also provides a member-number field for CT-1120CU filers.
- Amounts for current-year credits, prior-year carryforwards, credits applied to taxes, and any applicable shared, exchanged, refunded, or carried-back credits.
If claiming credits against more than one tax type, attach a separate Form CT-1120K and the applicable credit forms to each return for which a credit is claimed.
How to file
Electronically: File Form CT-1120K electronically with Form CT-1120 using myconneCT.
By mail: Complete the form in blue or black ink only. Do not use staples. Attach it to Form CT-1120 or the applicable tax form. The supplied text does not give a mailing address.
Use the correct year's form. This version is for 2024.
Use Part I to summarize the applicable credits. Use Part II for credits applied to the Corporation Business Tax and Part III for credits applied to other taxes. Enter the tax name in Part III. If applying credits to more than one tax other than the Corporation Business Tax, attach supplemental copies of Part III.
Transfer Part II, Line 9 to Form CT-1120, Schedule C, Line 5a, or the appropriate column of Form CT-1120CU, Part II, Line 3. Transfer Part III, Line 9 to the appropriate tax return.
Common mistakes
- Using the wrong year's form: The instructions warn that this can delay processing.
- Claiming the same credit more than once: The instructions expressly prohibit this.
- Applying credits out of order: Apply credits with carryback provisions first, credits with neither carryback nor carryforward provisions next, and credits with carryforward provisions after that. Apply the Electronic Data Processing Equipment Property Tax Credit last.
- Overlooking expiration order: Claim carrybacks and carryforwards that expire first before those that expire later. The form also says to use expiring carryforwards before those that do not expire.
- Including research-credit exchanges in the wrong total: Do not include Part I-C, Lines 16 and 17, Column G amounts in the Column G total on Line 29.
- Skipping the first housing-credit step: Complete Part I-A, Line 2 before claiming the Housing Program Contribution credit in Part I-C, Line 15.
- Exceeding the printed limits: Follow each line's limit. No credit can be applied against the $250 minimum tax.
Questions people ask
Do I need CT-1120K if I only have a prior-year credit balance?
Yes. The instructions require it when carryforward tax credit balances exist from a prior year, even if you are not claiming a current-year credit.
How much Corporation Business Tax can credits offset?
The general limit is 50.01% of tax due before credits. Remaining Research and Development, Research and Experimental Expenditures, and qualified Human Capital Investment credits may be used further, but total credits used cannot exceed 70% of the tax liability. No credit can offset the $250 minimum tax.
Can unused credits be carried back?
For the Neighborhood Assistance Act credit, a remaining balance may be carried back to the immediately preceding two income years. For the Housing Program Contribution credit, it may be carried back to the five immediately preceding income years. Claim a carryback by filing Form CT-1120X or the appropriate amended tax return.
Can combined unitary group members share credits?
Yes, subject to the printed sharing rules. Credits earned in the current year by a taxable member may be used by any group member. Prior-year credit sharing depends on the return filed and group membership in the year the credit was earned. Each taxable member remains individually subject to the credit limits and ordering rules.