Built for US CPAs

Every US tax deadline, every client, one calendar that stays in sync.

DueDateHQ derives a personalized filing calendar from your client book — federal, all 50 states, franchise, and PTE. An AI parser turns raw IRS and state relief announcements into "these N clients get 14 extra days" in one click, and a chat agent lets you query the book and execute changes from one prompt.

Free forever for up to 10 clients · Pro ships with a 14-day trial, no credit card

The pain

Deadline tracking is the boring, high-stakes glue work of every tax practice.

Spreadsheets don't scale to 50 states

Federal + state income + franchise + PTE elections mean hundreds of dates per client. One missed deadline is a penalty, a painful email, and a trust tax.

Relief announcements are scattered

IRS, FTB, TX Comptroller, ten other state DORs — every site is different. By the time you've figured out who's affected, the window is closing.

Your calendar apps don't know about any of this

Your clients live in QuickBooks or TaxDome, your deadlines live in spreadsheets, your schedule lives in Apple Calendar or Google. None of them talk to each other.

The product

A deadline system that earns its own maintenance cost.

300-rule deadline engine

Federal + all 50 states + 4 franchise regimes + 8 PTE elections. Every rule ships with a statutory citation and verbatim quote from the authoritative source.

Automatic regeneration when you edit a client's states or entity type
Weekend + federal-holiday roll-forward out of the box
Smart priority score — §6651 penalty + key-client flag + 90-day churn

AI-native chat agent

Ask DueDateHQ anything about your book at /assistant. Grok 4.1 Fast drives 8 read tools and 13 human-in-the-loop write tools, so you brainstorm and execute from the same prompt.

Generative-UI cards (Metric / Table / BarGraph / Alert …) instead of walls of text
Every mutation surfaces a confirm card — destructive ones need type-to-confirm
Launch with ⌘J, from the palette, or the sidebar

AI announcement parser

Paste a URL or raw text. Grok 4.1 Fast via OpenRouter extracts state, counties, entity types, new due date, and a confidence score before anything hits your inbox.

Structured Zod output with a confidence floor before it hits your inbox
Matcher groups clients by definite / likely / unlikely with per-client reasons
Bulk-apply extensions in one click, with an undo window

ICS calendar subscription

Generate a token-protected URL and paste it into Apple Calendar, Outlook, Fantastical, or Google “add by URL”. One-way, read-only, all-day events that refresh every few hours.

No OAuth calendar scope, no verification wait, no second consent screen
Stable per-deadline UIDs so subscribers dedupe across refreshes
Rotate or revoke the URL any time from Settings

How it works

Four steps from zero to a synchronized calendar.

Step 1
Sign in with Google
One click. Basic profile scope only — no Calendar write permission, no “unverified app” warning, no verification queue to wait out.
Step 2
Bring your clients in
Import from CSV (TaxDome, Drake, Karbon, QuickBooks, or Generic presets), or add them one at a time from the wizard.
Step 3
Pick your practice states
We regenerate the right 300-rule subset for every client: federal, state income, franchise, PTE.
Step 4
Let DueDateHQ do the glue work
Smart-priority dashboard, ICS calendar feed, email reminders, AI relief parsing, and an /assistant chat agent — all on by default.