Learn more about what to expect for the tax filing season including key deadlines, best practices, and answers to frequently asked tax questions.
Thank you for considering Founder's CPA for your individual tax return. This guide will give an overview of the key deadlines you should be aware of, best practices for your return, resources and some common FAQs. If you have further questions or concerns over anything below, don't hesitate to send us a message.
1/15/25 |
4th Quarter 2024 Estimated Tax Due |
1/16/24 |
Tax Proposals Sent + Organizers Uploaded/Sent |
4/15/25 |
Individual Tax Deadline – (Individuals, Trusts, C-Corporations, various state Pass-Through entities) - Returns or Extensions Must Be Filed |
4/15/25 |
1st Quarter Estimated Taxes Due |
6/16/25 |
2nd Quarter Estimated Taxes Due |
9/15/25 |
3rd Quarter Estimated Taxes Due |
10/15/25 |
Individual Tax Extension Deadline – (Individuals, Trusts, C-Corporations, various state Pass-Through entity returns) - Returns on Extension Must Be Filed |
1/15/26 |
4th Quarter 2025 Estimated Taxes Due |
Read below to find helpful resources from the IRS that you may need for the tax filing season. Please note that the IRS regularly updates their sites with pertinent information so please check on this regularly for any administrative changes or updates that you should be aware of.
Internal Client Communications
What happens if I don't sign my engagement letter by the signing date?
If you fail to sign your engagement letter by the signing date, you may be subject to disengagement and will be placed on a waiting list. Once on the waiting list, we cannot guarantee that we will have the capacity to file your return during the tax season.
How do I accept a proposal on Ignition?
Please follow these instructions: Ignition Proposal Instructions
What happens if I don't submit my documents by my assigned submission date?
If you don't submit your documents by your assigned submission date, you may be subject to disengagement per the terms and conditions of our engagement letter.
What if I don't sign the e-file authorization right away?
We cannot submit your tax return without the e-file authorization signed and submitted to us. Failure to do so in a timely manner means that we may not have time to submit your tax return before the e-file deadline. After the e-file deadline has passed, your return will have to be mailed in. Late filings may result in penalties from the IRS.
How do I log in to the SafeSend Tax Portal?
Go to this link: https://founderscpa.ssportal.com/
If you need additional help, follow these instructions to log into the SafeSend Tax Portal.
How do I upload documents to the SafeSend Tax Portal?
Go to this link: https://founderscpa.ssportal.com/
If you need additional help, follow these instructions on how to upload documents.
Can I mail in my documents?
Yes. We would prefer if you uploaded the documents to us via the SafeSend Tax Portal, but if you prefer to mail them, please mail ALL your documents at once to:
Founder's CPA
850 W Jackson, Suite 330
Chicago, IL 60607
Thank you for considering Founder's CPA for your business tax return. This guide will give an overview of the key deadlines you should be aware of, best practices for your return, resources and some common FAQs. If you have further questions or concerns over anything below, don't hesitate to send us a message.
1/16/24 |
Tax Proposals Sent + Organizers Uploaded/Sent |
1/31/25 |
W2 Form Filing Deadline |
1/31/25 |
1099 Form Filing Deadline |
3/1/25 |
DE C-Corp Filing Due |
3/17/25 |
Pass-Through Tax Deadline - (Partnerships, Multi-Member LLCs taxes as Partnerships, and S-Corporations) Returns or Extensions Must be Filed |
3/17/25 |
S-Corporation Election (Form 2553) Deadline |
4/15/25 |
Individual Tax Deadline – (Individuals, Trusts, C-Corporations, various state Pass-Through entities) - Returns or Extensions Must Be Filed |
4/15/25 |
1st Quarter Estimated Taxes Due |
5/15/25 |
Tax-Exempt Tax Deadline - Tax-Exempt entities(such as non-profits) - Returns or Extensions Must Be Filed |
6/1/25 |
DE LLC Filing Due |
6/16/25 |
2nd Quarter Estimated Taxes Due |
9/15/25 |
Pass-Through Extension Tax Deadline - (Partnerships, Multi-Member LLCs taxes as Partnerships, and S-Corporations) Returns on Extensions Must be Filed |
9/15/25 |
3rd Quarter Estimated Taxes Due |
9/30/25 |
Trust Returns on Extension Must Be Filed |
10/15/25 |
Individual Tax Extension Deadline – (Individuals, C-Corporations, various state Pass-Through entity returns) - Returns on Extension Must Be Filed |
1/15/26 |
Corporate 4th Quarter 2025 Estimated Taxes Due |
Read below to find helpful resources from the IRS that you may need for the tax filing season. Please note that the IRS regularly updates their sites with pertinent information so please check on this regularly for any administrative changes or updates that you should be aware of.
Penalties | Underpayment of Estimated Tax Penalty
Internal Client Communications
What happens if I don't sign my engagement letter by the signing date?
If you fail to sign your engagement letter by the signing date, you may be subject to disengagement and will be placed on a waiting list. Once on the waiting list, we cannot guarantee that we will have the capacity to file your return during the tax season.
How do I accept a proposal on Ignition?
Please follow these instructions: Ignition Proposal Instructions
What happens if I don't submit my documents by my assigned submission date?
If you don't submit your documents by your assigned submission date, you may be subject to disengagement per the terms and conditions of our engagement letter.
What if I don't sign the e-file authorization right away?
We cannot submit your tax return without the e-file authorization signed and submitted to us. Failure to do so in a timely manner means that we may not have time to submit your tax return before the e-file deadline. After the e-file deadline has passed, your return will have to be mailed in. Late filings may result in penalties from the IRS.
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