Rhode Island follows the federal calendar but adds a flat minimum tax that catches business filers off guard. For the 2025 tax year, individual and C-corporation returns are due April 15, 2026, and S-corporation and partnership returns are due March 16, 2026. The number to plan around is the $400 minimum tax, which applies to corporations and to most pass-through entities regardless of profit.

What are Rhode Island's 2026 tax filing deadlines?

For the 2025 tax year, the Rhode Island individual return (RI-1040) and C-corporation return (RI-1120C) are due April 15, 2026. S-corporations (RI-1120S) and partnerships (RI-1065) are due March 16, 2026, since the statutory March 15 date falls on a Sunday. One exception: a single-member LLC filing the RI-1065 follows the owner and is due April 15, 2026.

What is Rhode Island's $400 minimum tax?

Rhode Island charges a $400 minimum tax that is owed even in a loss year. It applies to C-corporations on the RI-1120C and to S-corporations and partnerships on the RI-1120S and RI-1065. Sole proprietors are not subject to it. A Rhode Island business entity should expect to owe at least $400 every year, which belongs in the client's expectations before the return is prepared.

How does Rhode Island's extension work?

Individuals get an automatic six-month extension to October 15, 2026 using Form RI-4868; businesses use Form BUS-EXT to reach September 15, 2026. In every case the extension is to file, not to pay. Tax, including the $400 minimum, is due on the original date.

What is Rhode Island's pass-through entity (PTE) election?

Rhode Island lets a pass-through entity elect to pay state tax at the entity level at 5.99%, which moves the deduction above the federal SALT cap. The election is made on RI Schedule PTE, filed with the RI-1120S or RI-1065, and members claim a corresponding Rhode Island credit. For clients hitting the SALT cap, this is the workaround to weigh before the March pass-through deadline.

How does Rhode Island tax nonresident pass-through owners?

The entity withholds. Rhode Island requires pass-through withholding on nonresident members, computed on RI Schedule PTW and filed with the entity return, at 5.99% for individual members and 7.0% for corporate members. Nonresident members may instead be included in a composite return on Form RI-1040C.

How does a firm handle Rhode Island at scale?

Two things to systematize. First, the $400 minimum means no Rhode Island entity files at zero, so build that floor into every business engagement. Second, the single-member-LLC exception puts some RI-1065 filers on April 15 instead of March 16, so the entity type drives the date. Track both, and flag PTE-election candidates before March. See how we think about scaling tax prep workflows.

Where do these dates come from?

All deadlines and thresholds here trace to the Rhode Island Division of Taxation. Verify against the source before filing.