The GRT location code determines which tax rate applies to your transaction. New Mexico has over 200 different codes, and rates vary significantly between jurisdictions. Santa Fe city has a different rate than unincorporated Santa Fe County. Taos is different from Española. Using the wrong code means you’re collecting and remitting at the wrong rate, which creates problems if you’re ever audited.

Since July 2021, New Mexico uses destination-based sourcing for most transactions. This means the location code is typically based on where your customer receives the goods or services, not where your business operates. A Santa Fe business completing a project in Los Alamos uses the Los Alamos location code for that work.

For physical goods, the code corresponds to where the customer takes possession. If they pick up at your shop, use your business location code. If you deliver to their address in Eldorado, use the Eldorado location code.

For services, the code is generally where the service is performed or delivered. A plumber working at a customer’s home uses that address for determining the code. A bookkeeper serving small business owners in Albuquerque uses the Albuquerque code for those clients, even if the bookkeeper’s office is in Santa Fe.

To find the actual code, use the New Mexico Taxation and Revenue Department’s location code lookup tool on their website. Enter the physical address where the transaction is sourced, and it returns the correct code along with the current rate. For addresses that straddle jurisdictions or fall in unincorporated areas, this tool is the authoritative source.

Some businesses still default to using their own business address code for everything. This was acceptable before the 2021 sourcing changes but is no longer correct for most transaction types. If you’ve been doing this, your filings need updating to reflect where transactions are actually sourced.

Track each transaction’s location code as part of your invoicing process. Trying to reconstruct which jobs happened where at the end of the quarter creates errors and takes time. Build it into your workflow from the start so the information is captured when you create the invoice or record the sale.

If your business involves multiple job sites or services performed at customer locations throughout Northern New Mexico, location code tracking becomes part of your regular accounting work. Setting up your accounting software to capture this information makes GRT return filing straightforward because the data is already organized by location. Getting the codes right from the beginning saves you from correcting filings later or explaining discrepancies during an audit.