Delaware Form PRT-PSI: the partner’s Schedule K-1 for 2025

Form PRT-PSI is Delaware’s own Schedule K-1 for partnerships. A partnership that files the Delaware partnership return, Form PRT-RTN, prepares one PRT-PSI for each person who was a partner at any time during the year, showing that partner’s share of income and deductions twice: once as the federal Schedule K-1 amount and once as the portion from Delaware sources. The current form is the 2025 PRT-PSI, Revision 20250730, published by the Delaware Division of Revenue.

Which partnerships prepare Form PRT-PSI

The 2025 PRT-RTN instructions (revised 05/27/25) say a partnership return must be completed by any business treated as a partnership for federal purposes that has income or loss, of any amount, derived from or connected with a Delaware source. A partnership with no Delaware-sourced income or loss does not file. Delaware-source income includes income from real or tangible personal property located in Delaware, from intangible property used in a business carried on in Delaware, and from a trade, business, profession or occupation conducted in Delaware.

The partnership itself is not taxed. Its partners owe Delaware personal income tax on their shares, and Form PRT-PSI is how each partner learns its share. The same section of the instructions sends partners to different returns:

• A Delaware resident partner files Form PIT-RES and reports the full share of partnership income or loss.
• A non-resident partner of a partnership with Delaware-source income files Form PIT-NON or a composite return and reports the share of Delaware-sourced partnership income or loss. On PIT-NON that goes on line 10, Column B, which the 2025 PIT-NON instructions describe as income or loss from property located in Delaware or from doing business in Delaware.

A typical case: a New Jersey resident holds 25% of a partnership that rents out a warehouse in Wilmington and also owns property in Pennsylvania. The partnership’s PRT-PSI for that partner shows the federal K-1 figures in Column A and only the Delaware-sourced part in Column B, and the partner carries the Delaware part to PIT-NON.

How to fill out the top of PRT-PSI

The form is a single fillable page. The numbers below follow the markers on the image, not printed line numbers; the printed lines 1 to 17 are covered in the next section.

The ITIN rule comes from the instructions; the printed check boxes read only EIN and SSN, and neither document says which box an ITIN filer checks.

PRT-PSI has no signature line. The partner’s signature and the paid preparer block are on page 2 of Form PRT-RTN.

The entity codes for marker 6 are printed on page 3 of the PRT-RTN instructions:

Lines 1 to 17: Column A and Column B

Every line has two amount boxes. Column A is headed “Federal 1065 Schedule K-1 Amount” (marker 9 on the image) and Column B “Portion of Items Derived from Sources in DE” (marker 10 for the income lines, marker 11 for the deductions). The line labels match Schedule 1 of Form PRT-RTN, which names the federal Form 1065 Schedule K line behind each item; the partner’s figure is the matching box of the 2025 federal Schedule K-1 (Form 1065).

Line 17 follows PRT-RTN line 20. A partnership operating a marijuana establishment under Chapter 13 of Title 4 or Chapter 49A of Title 16 may deduct ordinary and necessary business expenses only if they were not deductible federally because of section 280E of the Internal Revenue Code.

Line 16 also carries credits. Form BUS-CRS (Revision 20250528) tells a partnership to allocate its Delaware business tax credits from lines 28 and 33 among the partners and report each partner’s amount on line 16 of the PRT-PSI it gives that partner. A partner who receives credits then prepares a separate BUS-CRS of its own and works out the allowable credit against its own Delaware tax.

What Column B should add up to

The Column B rule is a single sentence on page 3 of the PRT-RTN instructions. For a Delaware resident, Column B should equal the total of lines 1 through 11 of the federal K-1. For a non-resident, it should equal the total of Column B (“Within Delaware”) from page 1, Schedule 1, lines 4 through 14 of the partnership return. For a resident partner that sentence and the form’s own Column B heading, which limits Column B to items derived from Delaware sources, point to different amounts: the full federal figures in one, the Delaware portion in the other. The instructions also do not say how a non-resident partner’s portion is carved out of the partnership’s Schedule 1 total; for a partnership doing business in Delaware and other states, Schedule 1 line 3 uses the apportionment percentage from Schedule 2, line 16, unless the partnership keeps separate accounting for its Delaware items. Formspedia does not choose between the two readings; the Division of Revenue can say which it expects before the forms go out (contacts at the end of this page).

When the partnership return is due and where it goes

The instructions say the partnership must prepare and give a PRT-PSI to each partner. They give no separate due date or mailing rule for the PRT-PSI itself; the dates that apply are those of Form PRT-RTN:

• PRT-RTN is due by the 15th day of the third month after the end of the taxable period, which is March 15 for a calendar-year partnership.
• Paper returns are mailed to the Delaware Division of Revenue, P.O. Box 8703, Wilmington, DE 19899-8703.
• A copy of the federal extension application submitted by that due date extends the Delaware return to the federal extended date; a photocopy of the approved federal extension must be attached to the return.
• A complete copy of federal Form 1065, with all schedules except the federal Schedule K-1, is attached to PRT-RTN.

Neither the instructions nor the forms page say whether copies of the PRT-PSI forms go to the Division with PRT-RTN. Ask the Division if you are unsure.