Due Days is the Mac app that ships with the 26 essential federal, California, shareholder, and corporate deadlines a typical California S corp owner tracks — and files the paperwork into your own folders as you check them off.
Free to join · Waitlist members lock in founder pricing · No spam, just the launch email
Due Days doesn't replace your CPA — it makes sure you know what's due and keeps the records your CPA will need.
The moment you elected S status, five separate calendars started running — and nobody handed you the master list.
Some dates are fixed. Some shift with weekends. Some are tied to your incorporation anniversary, and one quarter is skipped entirely. Missing just one can cost hundreds or thousands — and the penalties compound monthly. Due Days is built for owners who manage one business, not tax departments managing hundreds of entities. Not in California? The federal half applies nationwide, and every state item is editable — swap in your state's equivalents once and they recur every year.
Federal late-filing penalty for Form 1120-S — even when you owe no tax.
California franchise tax due every year, whether you remember it or not.
Typical count of federal, state, and corporate obligations for one CA S corp.
Three screens do all the work: the timeline, the yearly template, and the deadline editor. Or skip the tour and click around yourself:
The yearly template holds your recurring obligations. Each January, Due Days generates the whole year's timeline from it automatically — quarterly estimates, annual returns, even every-2-years items appear only in matching years.
Add anything your business has to remember — city license renewals, insurance, corporate minutes. Record the amount and the date you actually paid, and attach the confirmation right there.
Filter by jurisdiction, flip between month and quarter views, and see upcoming, overdue, and done counts at a glance. Everything you've filed shows the date and amount — a clean audit trail your CPA will love.
Due Days isn't another to-do app. It ships pre-loaded with the deadlines your business actually has, and it organizes the paperwork as you go.
Start with 26 real deadlines — 1120-S, CA Form 100S, quarterly estimates for you and the corp, 1099-NECs, Statement of Information, board minutes, insurance renewals. No blank-page setup.
Attach a confirmation or return to any deadline and Due Days saves it to your own folder — sorted by year, category, and filing. Tax season prep becomes "open the 2026 folder."
Every January the timeline regenerates from your template. And when the IRS or FTB shifts a date, the yearly deadline refresh updates your timeline for you — set it up once, it stays current.
Filter by jurisdiction in one click. Add your own deadlines — city business license, insurance renewals, whatever your business needs to remember.
Upcoming, overdue, and done counts sit at the top of the timeline. Mark items filed or paid, record what you paid and when — a clean audit trail for your CPA.
Everything lives on your Mac, in folders you control. No cloud account required, nothing to sync, nothing to leak. Disconnect the folder anytime — your files stay put.
Point Due Days at a folder like "Business Filings." That's where every attached document will be filed, neatly by year and deadline.
Start from the built-in S corp template, then add, remove, or edit anything. Your custom items join the yearly template automatically.
When a deadline comes up, file or pay it, drop the confirmation in, and mark it done. Amounts and dates are recorded for you.
Come April, everything your CPA needs is already organized in one folder — receipts, returns, dates, and amounts.
I own Pyramid Security Systems, a California S corp. Every season meant the same ritual: checking the IRS site, the FTB site, my CPA's emails, and my calendar — wondering what I'd forgotten this time. No single deadline was hard; keeping all of them in my head was. So I built the app I kept wishing existed: the whole year on one timeline, with the paperwork filing itself as I check things off. And because I run a security company, everything stays on your Mac — that part was never negotiable.
— Justin Rast, owner of Pyramid Security Systems Inc. & founder of Due Days
A late 1120-S runs $255 per shareholder, per month. Both plans start with a 14-day free trial at launch, and waitlist members lock in the founder rate for good.
Founder rate for waitlist members — locked in for as long as you subscribe
Limited to the first 250 customers — waitlist members get first claim before it opens publicly
Founder pricing is honored at launch — no payment now, no obligation. Either way your documents live in plain folders on your Mac, fully readable without the app.
No — Due Days is a deadline tracker and document organizer, not tax prep software. It tells you what's due, when, and keeps the paperwork organized. You (or your CPA) still do the actual filing. Think of it as the layer between your calendar and your filing cabinet.
The one-time license covers every v1.x release — bug fixes, improvements, and the yearly deadline-date refreshes — for as long as v1 exists. If a major v2 ships someday with big new capabilities, lifetime owners get discounted upgrade pricing, and v1 keeps working either way.
Sign up with your email and we'll send you a private launch link with founder pricing — $59/year (instead of $99), locked in for as long as you subscribe. Waitlist members also get first access to the 250 lifetime licenses at $249. No payment or commitment until launch day, and the rate is locked in once you buy.
Yes. Federal deadlines (1120-S, 1040-ES quarterlies, 1099-NEC) apply nationwide, and every item is editable — swap the California items for your state's equivalents and they'll recur every year via the template. More state templates are on the roadmap.
In a regular folder on your Mac that you choose — organized by year, category, and deadline. Due Days never uploads your documents anywhere. No cloud, no account, no server — your files are yours.
The subscription stays current forever — every new feature and every yearly deadline refresh, always. The lifetime license is for people who prefer owning software outright: pay once, use v1 for good. If you're unsure, join the waitlist — you don't have to decide until launch.
Your files never leave your Mac, so you keep everything — every document, in plain folders you can browse in Finder. The app simply stops generating new yearly timelines and receiving date updates.
Be first in line when Due Days launches — and lock in the discounted rate before it's gone.
Founder rate: $59/yr (reg. $99) or $249 lifetime · 14-day free trial · No payment until launch