# Special certificate types

Source: https://developer.avalara.com/products/ecm/integration-guides/document-management/rzq9923805323405/

Guide: Exemption Certificate Management (ECM)

# Special certificate types

Learn about different types of special certificates and their specific use cases.

The following outlines key considerations for handling multijurisdictional, single-use, and exemption percentage certificates. These certificates interact with Avalara systems and apply to specific business scenarios, such as utility purchases.

-   **Multijurisdictional certificates:**

    The exemption matrix controls the certificate that is presented during an ecommerce workflow. A customer presented with a multijurisdictional certificate can complete one certificate to cover multiple jurisdictions. Determine how best to handle more jurisdictions during validation and what information to display when retrieving customer exemption status.

-   **Single-use certificates:**

    If a product or a service only allows a single-use certificate, the site must call for a new certificate each time instead of using the API to retrieve the customer's status.

-   **Exemption percentage certificates for utility companies:**

    If a certificate exempts only a portion of the total tax, the site must calculate that percentage following certificate submission. The percentage of the exemption can be documented during the validation process, but it can't be automatically loaded into a tax engine for calculation.

    -   This function is applicable only for certain electrical utility purchases with the support of an approved engineering use report.

    -   This doesn’t apply to certain states with reduced sales tax forms, such as California manufacturing exemptions.

    -   Exemption percentages aren’t compatible with AvaTax. You can store an exemption percentage for informational purposes, but it doesn’t have any impact on tax calculation in AvaTax.