April is one of the heavier months on the compliance calendar. Q1 is behind you, quarterly filings are due, and tax season has everyone's attention — including state revenue departments. Here's how to stay on top of it.

Week of March 30 – April 3

Reconcile Q1 and March transaction data

• Pull reports from Shopify, Stripe, or your billing platform for both March and all of Q1.

• Cross-check collected tax against what's actually owed, state by state.

• Flag discrepancies now — chasing them down in week three is avoidable stress.

Review nexus status

• Did Q1 revenue push you across any new state thresholds?

• If you triggered nexus during the quarter, you'll need to register before you can file.

• Don't forget: some states require registration within 30 days of crossing a threshold.

Unclear about your tax exposure? Try our free Nexus study.

Week of April 7 – 11

Prepare monthly and quarterly filings

• Monthly filers: returns are typically due April 20th.

• Quarterly filers: Q1 returns are due in April. Confirm your specific due dates by state.

• Gather credentials for every state portal you're filing in.

• Confirm your collected tax is sitting in your account and matches what you'll remit.

Respond to any outstanding state notices

• Clear anything that came in during Q1: nexus questionnaires, compliance letters, or audit inquiries.

• Notices from March that haven't been addressed are already behind schedule.

Week of April 14 – 18

File monthly returns

• If you're filing in 10+ states manually, clear your calendar. This takes time.

• Don't overlook local jurisdictions! City and county-level returns can sneak up on you.

• Save confirmation numbers for every filing.

Review and refresh exemption certificates

• B2B sellers: check that exempt customer certificates are current and on file.

Week of April 21 – 25

Complete Q1 quarterly filings

• Most Q1 quarterly returns are due April 30th. Get them in early if possible.

• Double-check each state's specific deadline; a handful run on different schedules.

• Review your Q1 totals across all states before submitting to catch any data gaps.

Spot-check product taxability

• Did you launch any new products or SKUs in Q1?

• Product taxability rules vary by state and category. A quick review now is cheaper than an audit later.

Week of April 28 – 30

Start planning for Q2

• Quarterly filers: Q2 starts now. Begin organizing data from April so July doesn't sneak up on you.

• Check whether any states where you're approaching nexus thresholds might push you into monthly filing frequency for Q2.

Audit your process

• How many hours did sales tax take this month?

• If the answer is more than a few, it's worth asking whether your current setup is actually working.

A Note on April Specifics

⚠️ Louisiana filers: the new combined state and parish return system launched in February. If you're still adjusting to the new filing format, April is a good time to confirm your process is working correctly before Q2.

⚠️ Nevada filers: returns are now due on the 20th, not end of month. This applies to your March return due in April.

There's a Better Way to Handle All of This

April's compliance load is real. Between monthly filings, Q1 quarterlies, exemption reviews, and nexus monitoring, the average business filing in 15+ states can spend two to three days on this alone.

Kintsugi automates the work that doesn't need to be manual: nexus monitoring, return preparation, filing, and deadline tracking across all 50 states. When April rolls around, your checklist gets a lot shorter.

➡️ See how Kintsugi handles the compliance calendar for you.