IMPORTANT DEADLINE: Individuals, Corporations, S-Corps, Large Partnerships, Partnerships and International
2026-09-15
INDIVIDUALS: Make a payment of your 2026 estimated tax if you are not paying your income tax for the year through withholding (or won’t pay in enough tax that way). Use Form 1040-ES. This is the third installment date for estimated tax in 2026. For more information, see Pub. 505.
CORPORATIONS: For calendar year corporations, deposit the third installment of estimated income tax for 2026. A worksheet, Form 1120-W, is available to help you estimate your tax for the year.
S-CORPORATIONS: File a 2025 calendar year income tax return (Form 1120-S) and pay any tax, interest, and penalties due. This due date applies only if you timely requested an automatic 6-month extension of time to file the return. Provide each shareholder with a copy of their final or amended Schedule K-1 (Form 1120–S) or substitute Schedule K-1 (Form 1120–S).
PARTNERSHIPS & LARGE PARTNERSHIPS: File a 2025 calendar year return (Form 1065). This due date applies only if you timely requested an automatic 6-month extension. Otherwise, see March 15. Provide each partner with a copy of their final or amended Schedule K-1 (Form 1065) or substitute Schedule K-1 (Form 1065).
INTERNATIONAL: Final extended deadline to file Form 8804 if a 6-month extension was filed in March.
Final extended deadline for Form 1042 if a 6-month extension was filed in March.
Final extended deadline for Form 3520-A if a 6-month extension was filed in March.
For additional information on these deadlines or our international services and tax services, please click here to contact us.

IMPORTANT DEADLINE: Benefit Plans (12/31 year end)
2026-09-30
BENEFIT PLAN DEADLINE (12/31 year end):
Summary Annual Report (SAR). Later of nine months after close of plan year or two months after due date of Form 5500. The extended due date is December 15.
For additional information on these deadlines or our employee benefit plan audit services, please click here to contact us.

IMPORTANT DEADLINE: Trusts
2026-09-30
Must file a completed 2026 tax return if a 5-1/2-month extension was filed in April.
For additional information on these deadlines or our estate and trust services and tax services, please click here to contact us.

Cancer Support Community Delaware: Cocktails for a Cause Sponsor
2026-11-12 18:00 - 19:30 (America/New_York) | Cancer Support Community Delaware, 4810 Lancaster Pike, Wilmington, Delaware, 19807
BLS is a Print Sponsor for Cancer Support Community Delaware’s 2026 Cocktails for a Cause.
Celebrate three decades of support, hope, and community, while we mark Cancer Support Community Delaware’s 30th year as an organization at Cocktails for a Cause on November 12th, 2026. Set against the stunning and historic grounds of our New Castle headquarters, this special evening will bring together supporters, friends, and community members for an unforgettable night of cocktails, hors d’oeuvres, and music.
Raise a glass in honor of the many lives touched by cancer and the critical programs that Cancer Support Community Delaware provides to those affected. Enjoy delicious cocktails and savory bites while mingling with fellow supporters, sharing stories, and celebrating our shared mission to offer emotional and social support to cancer patients, survivors, and their families.
Learn more here: Cancer Support Community Delaware 2026 Cocktails for a Cause.
