Taxjar
TaxJar provides a comprehensive sales tax API for real-time tax calculations, reporting, and filing.
Verdict
Common use cases
- Calculate checkout tax in real time
- Log completed orders for compliance
- Record refunds and adjust tax liability
- Audit nexus states before expansion
- Retrieve customer exemption certificates
Integration
- Vendor
- Taxjar
- Category
- other
- Auth
- API_KEY
- Tools
- 18
- Composio slug
taxjar
Tools
- Calculate Sales Tax For An Order
Tool to calculate sales tax for an order. use when you need an accurate tax calculation including nexus addresses, line items, shipping, and exemptions.
- Create Order Transaction
Tool to create a new order transaction. use after preparing transaction details.
- Create Refund Transaction
Tool to create a new refund transaction. use after confirming refund details.
- Delete Customerdestructive
Tool to delete an existing customer. use when you need to remove a previously created customer by its id. example: "delete customer cust 12345".
- Delete Order Transactiondestructive
Tool to delete an existing order transaction. use when you need to remove a previously created order transaction by its id. example: "delete transaction abc123".
- Delete Refund Transactiondestructive
Tool to delete an existing refund transaction. use when you need to remove a previously created refund transaction by its id. example: "delete refund 243345".
- List Customers
Tool to list existing customers. use when you need to retrieve customer records after they are created.
- List Nexus Regions
Tool to list existing nexus regions for an account. use after authenticating your account to discover where you have nexus for sales tax purposes.
- List Order Transactions
Tool to list existing order transactions. use when you need to retrieve created orders for reporting or analysis.
- List refund transactions
Tool to list refund transactions. use when you need to retrieve refunds created through the taxjar api.
- List Tax Categories
Tool to list all product tax categories and their codes. use when you need to discover available tax categories before assigning them to products.
- Show Customer
Tool to show an existing customer. use when you need to retrieve details of a specific customer via taxjar api.
- Show Order Transaction
Tool to show an existing order transaction by id. use when you need to retrieve full details of a specific order transaction after creation or listing.
- Show Refund Transaction
Tool to show a refund transaction. use when you need to retrieve details of an existing refund transaction via taxjar api.
- Show Tax Rates for a Location
Tool to show sales tax rates for a location. use when you need to retrieve sales tax rates for a specific zip code with optional address details (city, state, country, street).
- Summarize Tax Rates for All Regions
Tool to retrieve minimum and average sales tax rates by region. use when you need a backup of regional tax summary rates.
- Update Order Transaction
Tool to update an existing order transaction. use when adjusting order details such as amount, shipping, or line items after creation.
- Validate VAT Number
Tool to validate a vat number for tax-exempt status. use when you need to confirm a vat number's validity and existence before applying tax exemptions.
Setup
Setup guide
- 11. Open your Switchy workspace settings and navigate to the Integrations tab. 2. Click Add Integration and select TaxJar from the list. 3. Log into your TaxJar account at taxjar.com, go to Account → API Access, and generate a new API token with transaction and customer permissions. 4. Paste the token into Switchy's connection dialog and click Connect. 5. Return to any Space, type '@TaxJar list nexus regions' and send the message. 6. If the MCP returns a list of states or provinces, the connection is live. 7. To calculate tax for an order, @mention TaxJar with the destination address, line items, and shipping cost; it will return the tax amount and jurisdiction breakdown you need for checkout or invoicing.
What teammates see: by default, memories from Taxjar are scoped to the Space (PROJECT visibility) - you can mark any memory PRIVATE or share it ORG-wide.
Works well with
Top models
Compatibility data appears once enough Spaces have used this MCP together with a given model.
How Switchy teams use it
Starter prompts
Calculate Order Tax
@TaxJar calculate sales tax for an order shipping to 123 Main St, Austin TX 78701 with line items: 2x Widget at $50 each, 1x Gadget at $120, and $15 ground shipping.Open in a Space →
Log Completed Sale
@TaxJar create an order transaction for order #ORD-4521 dated today, customer ID cust_789, total $235 including $18.80 tax, shipped to Denver CO.Open in a Space →
Record Customer Refund
@TaxJar create a refund transaction for original order #ORD-4521, refund ID REF-9988, amount $120 including $9.60 tax, processed today.Open in a Space →
Check Nexus States
@TaxJar list all nexus regions for my account and show the effective dates for each jurisdiction.Open in a Space →
Retrieve Customer List
@TaxJar list all customers in my account and include their exemption type if one is on file.Open in a Space →
Example outputs
Illustrative - representative of the model's voice and quality, not literal recordings.
@taxjar calculate sales tax for an order shipping to 123 Main St, Austin TX 78701 with $150 in products and $10 shipping
Based on the Austin, TX delivery address, the calculated sales tax is $13.20 (8.25% rate). This includes Texas state tax (6.25%) plus Travis County and Austin city taxes (2.00%). The taxable amount of $160.00 includes both product subtotal and shipping. TaxJar applied nexus rules for your account and determined this order creates tax obligation in Texas.
This example shows TaxJar's core calculation engine in action. The accuracy depends on your nexus configuration being up-to-date in TaxJar's dashboard. Rates change quarterly in some jurisdictions, so treat calculations as estimates until the transaction is finalized. API key must have calculation permissions.
@taxjar create an order transaction for order #ORD-2847 placed today: customer ID cust_9234, shipped to Seattle WA, $200 product total, $15 shipping, $18.53 tax collected
Order transaction ORD-2847 created successfully in TaxJar. Recorded $200.00 in sales, $15.00 shipping, and $18.53 tax collected for Seattle, WA. This transaction is now part of your sales tax reporting and will appear in your next filing period summary. TaxJar linked it to customer cust_9234 and applied Washington state nexus rules.
This write operation permanently records the transaction in TaxJar for compliance reporting. Once created, you'll need the transaction ID to update or delete it later. Make sure the tax amount you collected matches TaxJar's calculation to avoid discrepancies during filing. Requires write scope on your API key.
@taxjar list all nexus regions for my account, then summarize which states require me to collect sales tax and flag any that have economic nexus thresholds I'm approaching
Your TaxJar account shows nexus in 8 states: California, Texas, New York (physical nexus from warehouses), plus Florida, Washington, Illinois, Georgia, and Ohio (economic nexus triggered). Florida and Ohio are flagged as approaching thresholds—Florida shows $950K in trailing 12-month sales against a $1M threshold, and Ohio shows 180 transactions against a 200-transaction trigger. You should monitor these monthly to avoid surprise nexus creation.
This synthesis example combines TaxJar's nexus data with the AI's ability to interpret thresholds and flag risks. The economic nexus rules are complex and change frequently, so verify current thresholds in TaxJar's dashboard before making compliance decisions. This read-only operation requires list permissions but provides strategic visibility into your tax obligations.
Use-case deep-dives
When TaxJar wins for real-time checkout flows
A 6-person DTC brand runs checkout on Shopify but needs accurate multi-state tax calculations before the customer hits 'pay'. The Calculate Sales Tax tool handles nexus logic, line-item breakdowns, and exemption certificates in one call—no need to maintain your own rate tables or nexus rules. This MCP is the right call if you're processing under 10k orders a month and your cart already collects the address and line-item data TaxJar needs. Above that volume, you'll want TaxJar's native Shopify app for better rate-limiting and webhook support. If your team is just reconciling tax after the fact in QuickBooks, skip this—TaxJar's reporting UI is faster than scripting transaction imports through the MCP.
When this MCP handles refund tax adjustments
A 3-person support team at a B2C SaaS company processes 40-60 refunds a week, and each refund needs a matching tax adjustment in TaxJar to keep their nexus filings clean. The Create Refund Transaction and Delete Refund Transaction tools let the team script refund workflows in Switchy without logging into TaxJar's dashboard for every case. This works if your refund volume is predictable and your support tool (like Zendesk or Intercom) already surfaces the original order ID. If refunds are rare or your accountant handles them in batch at month-end, the manual UI is less overhead than maintaining the MCP connection. Use this when refund speed matters for customer experience and you want support to own the full loop.
When you need customer tax status in sales calls
A 5-person sales team at a B2B marketplace closes deals with tax-exempt nonprofits and resellers, and reps need to confirm exemption status live on calls before quoting a final price. The List Customers tool pulls the exemption certificate on file so the rep doesn't have to ping finance or dig through TaxJar's UI mid-conversation. This MCP is the right call if your customer count is under 5k and exemption status changes infrequently—above that, the list endpoint gets slow and you'll want a cached lookup table instead. If your sales team rarely quotes tax or your CRM already syncs exemption flags, skip the MCP and use TaxJar's native CRM integrations. Use this when deal velocity depends on instant tax clarity.
Frequently asked
What does the TaxJar MCP do in Switchy?
It calculates US sales tax for orders, manages transaction records, and tracks nexus regions where your business owes tax. You can ask Switchy to compute tax for a cart, log completed orders, process refunds, or check which states trigger collection obligations. It's useful for e-commerce teams that need real-time tax math without switching to TaxJar's dashboard.
Do I need a TaxJar account to use this MCP?
Yes. You'll need an active TaxJar subscription and an API key from your account settings. The MCP authenticates with that key, so whoever connects it must have admin access to generate tokens. Free trial keys work during the trial period, but rate limits apply.
Can it file sales tax returns for me?
No. This MCP handles calculations, transaction logging, and nexus lookups—it doesn't submit returns to state agencies. TaxJar's AutoFile feature lives in their web app, not the API. Use Switchy to prep the data, then file through TaxJar's dashboard or their separate filing service.
How is this different from calling TaxJar's API directly?
You describe what you need in plain English instead of writing HTTP requests. Switchy handles parameter formatting, error retries, and combines multiple tool calls if you ask a complex question. The trade-off: you're limited to the 18 tools the MCP exposes, not TaxJar's full REST surface.
Who on my team should connect the TaxJar MCP?
Whoever owns your TaxJar account and can generate API keys—usually finance or operations. Once connected, any Switchy workspace member can ask tax questions or log transactions. Consider creating a read-only key if you only want calculations, not transaction writes.