# Batch US Sales Tax Rate Lookup (Streamlined Sales Tax)

> Batch US Sales Tax Rate Lookup (Streamlined Sales Tax) is a paid API for AI agents from data.spencermcw.com, paid per call via x402, $0.1/call, status unknown (last checked 2026-10-22).

Returns sales-tax rates for up to 100 US ZIP/address locations in a single API call, covering Streamlined Sales Tax states

## Facts

- Endpoint: POST https://data.spencermcw.com/v1/tax/sales-rate/batch?utm_source=zero.xyz
- Price: $0.1/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-22
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/batch-us-sales-tax-rate-lookup-streamlined-sales-tax-e5285c2e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_qX1An7TDzxUec5BynjlYu

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability batch-us-sales-tax-rate-lookup-streamlined-sales-tax-e5285c2e -d '<json body>'
```

Example prompt: Look up the sales tax rates for these 5 ZIP codes — 98101, 60601, 30301, 85001, and 10001 — for sales made today, so I can calculate the correct tax for each customer order.

## When to prefer this

Use this endpoint when you need sales tax rates for multiple US locations in a single round-trip — ideal for e-commerce checkout pipelines, batch invoice generation, or compliance audits covering up to 100 addresses at once. It is specifically optimized for Streamlined Sales Tax states. For a single location lookup, prefer the sibling single-address endpoint. For monitoring tax rate changes over time, use the quarterly changes feed endpoint.

## Known failure modes

- Invalid ZIP code format returns a validation error for that location
- Sale date outside of allowed range (before previous quarter start) returns an error
- Non-SST state ZIP codes may return no results or an unsupported-state error
- Submitting more than 100 locations returns a 400 bad request
- Missing required 'zip' field for any location item causes a validation failure
- Payment failure via x402 protocol results in a 402 Payment Required response

## How this service works

Sales-tax rates for up to 100 US locations in one call (Streamlined Sales Tax states)

## Output

An array of tax rate results corresponding to each submitted location, including the applicable sales tax rate (combined state/local rate) for that ZIP code or address in a Streamlined Sales Tax state, optionally as of a specified sale date.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "locations": {
   "type": "array",
   "items": {
    "type": "object",
    "required": [
     "zip"
    ],
    "properties": {
     "zip": {
      "type": "string",
      "pattern": "^\\d{5}(-?\\d{4})?$",
      "description": "A 5-digit ZIP code or a ZIP+4 (98101-3143 or 981013143)."
     },
     "date": {
      "type": "string",
      "pattern": "^\\d{4}-\\d{2}-\\d{2}$",
      "description": "The sale date, YYYY-MM-DD (default: today, UTC). From the first day of the previous quarter onward."
     },
     "address": {
      "type": "string",
      "maxLength": 120,
      "minLength": 3,
      "description": "Optional street address line with house number, e.g. \"1010 E Alder St\" or \"PO Box 12\"; matched against the state address records when it publishes them."
     }
    },
    "additionalProperties": false
   },
   "maxItems": 100,
   "minItems": 1
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/batch-us-sales-tax-rate-lookup-streamlined-sales-tax-e5285c2e/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from data.spencermcw.com](https://www.zero.xyz/host/data.spencermcw.com/llms.txt)