Illinois PTET 2026: deadline, rate, who can elect
Illinois (IL), tax year 2026, from the same rules the connector returns. 2025 is below for comparison. Last verified October 24, 2026.
Informational. Not tax advice.
Elective PTET
Yes
The PTE tax continues for tax years ending on or after December 31, 2021, and FY 2026-15 says Public Act 104-0453 removed the expiration.
Who can elect
A partnership other than a publicly traded partnership under IRC 7704, and a subchapter S corporation.
The resident-base election in FY 2027-01 is stated for partnerships, not for S corporations.
How the election is made
Annual election on Form IL-1065 or Form IL-1120-ST, irrevocable after the extended due date. For a tax year ending on or after December 31, 2026, an electing partnership may also choose its tax base under 35 ILCS 5/201(p)(2.1).
Public Act 104-0468, described in FY 2027-01, lets the partnership choose the Illinois-sourced portion of all partners' distributive shares, or the full distributive shares of resident partners plus the Illinois-sourced income of nonresident partners. The choice is on Form IL-1065. Estimates differ by method. The bulletin does not give S corporations this choice.
Election deadline
On the return, irrevocable after the extended due date. The return is generally due the 15th day of the fourth month after year-end. An automatic six-month filing extension does not extend payment.
Calendar-year original due date is April 15.
Rate
4.95 percent of the electing entity's net income.
The credit is 4.95 percent of the owner's distributive share and is considered paid on the last day of the entity's tax year. The 2026 base election changes what income is in the tax, not this rate.
Owner relief
Credit, not an exclusion. 4.95 percent of the owner's distributive share of the electing entity's net income, reported on Schedule K-1-P.
The credit is treated as paid on the last day of the entity's tax year.
Estimates
Quarterly if expected PTE tax plus replacement tax is more than $500. For a 2026 partnership base election, FY 2027-01 says the estimate computation follows the base the partnership selected.
Required payment is 90 percent of current-year liability or 100 percent of prior-year liability. Electronic payment is required if annual tax liability including the PTE tax is at least $20,000. No election means no PTE estimates.
Sunset or repeal
The prior expiration was removed by Public Act 104-0453. No replacement sunset date was confirmed in the statute text reviewed.
FY 2026-15 is the source for the removal. The tax is still described as available for years ending on or after December 31, 2021.
Still open in the source review
- The Illinois add-back percentage for IRC 168(k) is not stated in FY 2026-15.
- IRC 179 treatment was not verified.
- The IRC conformity date was not verified.
- Public Act 104-0453 removed the PTE expiration. No replacement sunset date was confirmed in the statute text reviewed.
Sources for this year
2025
Last verified October 24, 2026.
Elective PTET
Yes
The elective pass-through entity tax under 35 ILCS 5/201(p) applies to years ending on or after December 31, 2021. FY 2026-15 states that Public Act 104-0453 removed the expiration date.
Who can elect
A partnership other than a publicly traded partnership under IRC 7704, and a subchapter S corporation.
Publication 129 and the Department Q&A describe those eligible entities.
How the election is made
The entity makes an annual election on Form IL-1065 or Form IL-1120-ST. The election is irrevocable after the extended due date of the return and applies to all partners and shareholders.
The 2026 choice between an Illinois-sourced base and a resident-inclusive base is not in this 2025 file. FY 2027-01 limits that choice to tax years ending on or after December 31, 2026.
Election deadline
Verify with the source. The pass-through page says the election is irrevocable after the extended due date. It does not state April 15 or the 15th day of the fourth month. Left unverified.
The election is made on the return and is irrevocable after the extended due date. The return is generally due the 15th day of the fourth month after year-end, April 15 for a calendar year, with an automatic six-month filing extension.
The extension does not extend the time to pay. Payment remains due on the original due date.
Rate
4.95 percent of the electing entity's net income.
Each partner or shareholder receives a credit of 4.95 percent of that owner's distributive share of the electing entity's net income. The credit is considered paid on the last day of the entity's tax year and is reported on Schedule K-1-P.
Owner relief
Credit, not an exclusion. 4.95 percent of the owner's distributive share of the electing entity's net income.
The credit is treated as paid on the last day of the entity's tax year.
Estimates
If expected tax, including the PTE tax and replacement tax, is more than $500, pay quarterly on the 15th of the fourth, sixth, ninth, and twelfth months.
The required payment is 90 percent of the current-year liability or 100 percent of the prior-year liability. Pay electronically if the annual tax liability, including the PTE tax, is at least $20,000. If the entity does not elect, these PTE estimates are not required.
Sunset or repeal
The prior expiration was removed by Public Act 104-0453. No replacement sunset date was confirmed in the statute text reviewed.
FY 2026-15 is the Department's statement that the expiration date has been removed. A credits-list date was not used. The tax remains available for 2025 under Publication 129.
Still open in the source review
- The Illinois add-back percentage for IRC 168(k) is not stated in FY 2026-15.
- IRC 179 treatment was not verified.
- The IRC conformity date was not verified.
- FY 2026-15 applies the IRC 168(n) decoupling to tax years beginning on or after January 1, 2026, and does not state a 2025 computation.
- Public Act 104-0453 removed the PTE expiration. No replacement sunset date was confirmed in the statute text reviewed.
Sources for this year
Bonus-depreciation conformity is on its own page.