Avalara AvaTax Integration: Setup and Sync

Connect Avalara AvaTax to DualEntry so sales tax is calculated automatically when you create an invoice, sales order, cash sale, or customer credit. The integration pulls your AvaTax companies and nexuses into DualEntry, then calls AvaTax in real time during transaction entry to determine the correct tax rate and amount based on the customer’s shipping address.

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Prerequisites

Confirm the following before connecting:

• An active Avalara AvaTax account, with your Account ID and License Key available.
• The companies you want to use exist in both DualEntry and AvaTax. DualEntry does not auto-create companies in AvaTax.
• Tax nexuses are configured in AvaTax for every jurisdiction where you collect tax.
• You know how each DualEntry company should map to an AvaTax company.

You also need a list of the AvaTax product tax codes you plan to use, so you can attach them to the corresponding DualEntry items during setup.

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Step 1: Connect the integration

Authorize DualEntry to call AvaTax with your account credentials.

1. Navigate to Configuration → Company → Integrations → Avalara.
2. Enter your Avalara Account ID and License Key.
3. Choose the environment: Sandbox or Production.
4. Choose Connect. DualEntry validates the credentials against AvaTax and confirms the connection.

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Step 2: Run the initial sync

After connecting, DualEntry pulls reference data from AvaTax automatically:

• The list of AvaTax companies on your account.
• The tax nexuses configured for each company.
• Custom tax codes (optional, if your AvaTax account uses them).

The sync is on-demand from this point on. To refresh the data, choose Sync from the Avalara integration page.

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Step 3: Map companies

Each DualEntry company must be mapped to a corresponding AvaTax company before transactions can be taxed.

1. Open Configuration → Company → Integrations → Avalara → Companies.
2. For each DualEntry company, choose the AvaTax company it corresponds to. The DualEntry company_id is sent to AvaTax as the company code on every transaction.
3. Save the mapping.

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Step 4: Confirm nexus matching

DualEntry auto-matches nexuses by country plus region or state. For example, AvaTax US-CA matches DualEntry US-CA. Global nexuses where country equals region (e.g., US-US) are skipped.

1. Open Configuration → Company → Integrations → Avalara → Nexuses.
2. Review the matched nexuses for each company.
3. If a nexus is missing, create it in AvaTax and run Sync again.

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Step 5: Set up product tax codes

Map the AvaTax product tax codes you plan to use, then attach them to your DualEntry items so AvaTax can apply the correct exemptions or reduced rates.

1. Open Configuration → Tax Setup → Product Tax Codes and add each AvaTax tax code you plan to use.
2. On each DualEntry item, set the Product Tax Code field to the appropriate code.
3. On each DualEntry customer, set the customer as Taxable or Tax Exempt.

Items without a tax code fall back to AvaTax’s DEFAULT taxable code.

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Step 6: Validate and go live

Once mappings are in place, confirm the integration is ready for transaction flow.

1. Verify every active DualEntry company is mapped to an AvaTax company.
2. Verify every required nexus is matched.
3. Verify items that need specific tax treatment have a product tax code assigned.
4. The integration is now marked Setup Complete, and tax is calculated automatically on new transactions.

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What syncs

The integration moves reference data one way and calls AvaTax in real time for tax calculation: Tax is calculated when you create any of these transaction types: invoice, sales_order, cash_sale, customer_credit. The customer’s shipping address determines the jurisdiction.

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Mapping reference

The integration relies on the following field mappings between AvaTax and DualEntry. Company mapping Nexus mapping Tax code mapping

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Current limitations

A few aspects of the integration are worth knowing before you rely on it:

• Posted transactions only. Draft transactions do not call AvaTax; tax is calculated on post.
• Shipping address required. Customers without a complete ship-to address cannot be taxed accurately. Verify ship-to and ship-from addresses on every taxable transaction.
• One-way reference sync. DualEntry does not push companies, customers, or items into AvaTax. Both systems must be configured independently.

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Troubleshoot tax calculation errors

When AvaTax returns an error or tax does not appear on a transaction, the most common causes are:

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Result

After completing these steps, sales tax is calculated automatically and accurately on every invoice, sales order, cash sale, and customer credit you post in DualEntry. To connect more systems, return to Integrations. To configure the customer and item records that feed tax calculation, see Accounts Receivable.