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Transitioning from SST to Kintsugi

What to expect and what we need from you
Updated last month

What Is SST and Why It Affects Your Move to Kintsugi

SST (Streamlined Sales Tax) is a multi-state program used by 24 states that allows one Certified Service Provider (CSP), like Avalara, to register, file, and remit on your behalf. Kintsugi is not a CSP. We file directly with each state, which means your SST registrations must be closed and replaced with standard state accounts before Kintsugi can take over.

Important: On the 1st of every month, your current CSP locks in that month's filings. To avoid duplicate filings or a missed period, you must deregister from your previous sales tax provider (i.e. Avalara) by the 20th of the month before Kintsugi starts. For example, for Kintsugi to handle May filings, deregister by April 20th.


What We Need From You

1. Tell Your Previous Provider to Deregister You from SST

Contact your previous sales tax provider and ask them to:

  • Remove you from SST in every state where you are registered

  • Disable all auto-payments and auto-filings for the upcoming cycle

  • Confirm the effective closure date in writing and share it with your Onboarding Manager

2. Share Your Account Details

  • List of states with active SST registrations

  • State Tax IDs for each of those states

  • Any existing state portal login credentials (if you don't have them, that's normal; we'll help you obtain them)

  • Copies of your last 3 months of filed returns per state

3. Retrieve State Portal Logins

Under SST, your previous provider likely handled logins centrally. To file directly, a state needs a relationship with you. Two options:

  • Option A: Contact each state's Department of Revenue directly and request portal access. Have a recent return ready for identity verification.

  • Option B: Ask your previous provider to share with you all state Tax IDs, Webfile numbers, and any login credentials on file.

4. Set Up Kintsugi Mail Before Cutover

Once standard state accounts are active, states will send physical notices to you. Kintsugi Mail lets us receive and act on those on your behalf from day one.

Timeline and Filing Handoff

Here is the typical sequence we follow, so you know what to expect from each side.

When

Who

What happens

Before the 20th of the month

You

Notify your previous provider to deregister from SST. Disable auto-pay. Confirm closure date.

Before the 1st of the next month

You + Kintsugi

Confirm the SST portal no longer lists your previous provider as your CSP. Share state IDs and any logins.

On the 1st of the next month

Kintsugi

We start as your filer of record. Standard state accounts are opened or linked.

First filing cycle with Kintsugi

Kintsugi

We file your first returns and watch closely for state notices.

Note: This timeline is feasible 90% of the time and the best thing you can do to stay on track is to contact your state revenue departments for your credentials as soon as possible. Keep in mind that registering in multiple states may cause 1–2 states to lag due to state processes. In this case, we automatically request a penalty and interest waiver on your behalf, subject to the state’s approval.

Some states will not release account IDs over the phone and mail them instead, which can take longer, especially if your address on file needs to be updated. Without a proactive approach, the process can take 4–8 weeks. We encourage you to complete your action items as soon as possible to ensure a smoother transition.


Historical Liability and Backfiling

  • Anything your previous provider has already filed stays filed by them, as we do not re-file completed returns.

  • Any period after your Kintsugi start date is our responsibility.

  • If you have unfiled periods or historical exposure, let us know.

  • Penalty or interest notices for periods filed by your previous provider should go back to them. Forward any state notices to your Onboarding Manager, and we will help you triage.

Note: When some states close an SST account and reopen a standard account, they may reset your filing frequency. If that happens, contact the state to request your preferred frequency, and we will update it on our side once confirmed.

Your Checklist

  • Contact your previous provider and request SST deregistration by the 20th of the month.

  • Confirm the effective closure date with your previous provider and share it with your Onboarding Manager.

  • Send your Onboarding Manager the list of SST states, state Tax IDs, and any logins you have.

  • Pull copies of your last 3 months of filed returns for each state.

  • Set up Kintsugi Mail.

  • Flag any historical exposure, including unfiled periods, notices, or audits, so we can scope it.

Need Help?

Questions? Reach out to your Onboarding Manager. We are here to make this easy for you.


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