Spaw vs PostGrid
PostGrid sells an address verification API for the United States and Canada, CASS and SERP certified against USPS and Canada Post data, with an international service for "245+ Countries and Territories", autocomplete, parsing, batch verification and a Salesforce integration, priced by quotation.
The table uses PostGrid's public pricing and documentation pages as checked on 2026-09-16, and Spaw's own pricing page. A row those pages carry no value for is marked "not on the pages read" rather than guessed at, and that is a statement about the reading and not about what PostGrid publishes.
| spaw | postgrid | |
|---|---|---|
| Pricing model | Pay-as-you-go credit packs whose credits never expire, or optional plans, billed monthly or yearly, that deposit the same credits every month for less and roll unused plan credits over up to three months' allowance; both through Stripe Checkout | Quoted: the pricing page asks for annual mail-piece and address-verification volumes in bands from "Less than 50,000" to "More than 1,000,000" and publishes no rate. |
| Free tier | 100 free credits every month, no card required | "Try for Free. Sign Up for Address Verification API" on the product page; no standing free volume is stated. |
| Price per 1,000 at about 10k | $7.80 (Growth pack: 5,000 credits for $39), or $5.80 on the Growth monthly plan (5,000 credits for $29 a month) | not on the pages read |
| Price per 1,000 at about 100k | $4.49 (Volume pack: 100,000 credits for $449), or $3.49 on the Volume monthly plan (100,000 credits for $349 a month) | not on the pages read |
| Addresses no register covered billed | An address that stands as written costs 1 credit whether or not a register carried the building; where no register covers the country, exists answers null rather than a verdict | not on the pages read |
| Addresses that cannot stand billed | No: an address that cannot stand as written is free whatever the reason, and so are repeats within 7 days and rows repeating an address already in the same job | not on the pages read |
| Registers held | Open address registers for 23 countries and territories, each named in the answer with its declared coverage, complete or partial. Complete, building by building: Australia, Austria, Belgium, Czechia, Latvia, Luxembourg, Netherlands, Norway and Switzerland. Partial, building by building: Brazil, Denmark, France (with French Guiana, Guadeloupe, Martinique, Mayotte, Réunion, St. Barthélemy, St. Martin and St. Pierre & Miquelon), Germany and United States. Partial, streets only: Great Britain. House-number ranges as well: United States. Absence from a partial register is never read as evidence that an address does not exist. | Postal: "CASS & SERP Certified", matching "customer addresses with official postal records from USPS and Canada Post"; also "CASS/NCOA Certified". |
| Country coverage | Postal formats for 207 countries and territories: the line layout for 199 of them, and the required fields and postcode pattern wherever the table records them; 52 postal operators' rules for naming a delivery point that is not a street; open address registers for 23 countries and territories; postcode directories for Great Britain from the ONS Postcode Directory, with Northern Ireland excluded because reusing BT postcodes needs a separate licence, and for 108 more countries and territories from GeoNames' postal codes. | "245+ Countries and Territories" for the international service; the standard API covers the United States and Canada. |
| Claims post is delivered | No, and every answer says so: is_deliverable, is_cmra, is_vacant and is_residential answer null because that check is licensed and not enabled here. exists is a match in an open address register, never a statement that post arrives. | Yes for the United States and Canada: an address comes back "Verified", "Corrected" or "Failed" against USPS and Canada Post data, and the CASS description names ZIP+4, carrier route and delivery point lookup. |
| Bulk limit | 100,000 addresses per bulk job, with an HMAC-signed completion webhook | not on the pages read |
| Batch API | 100 addresses per synchronous request | Yes: "Process large datasets at once via the /verifications/batch endpoint"; no limit is stated on the page. |
| Rate limit | 50 requests per second per key on the address endpoints | not on the pages read |
| Official SDKs | Python, Node.js, PHP | not on the pages read |
| Data retention | No history row and no log line carrying the address. What a lookup leaves is the 7-day marker that makes a repeat free and the count behind seen_by_you, both kept under a digest, never the address. The address itself is kept only on the account's own suppression list and in its monitors. Bulk input lists and result files are deleted with the job after 30 days. | not on the pages read |
checked 2026-09-16 · sources: PostGrid pricing, PostGrid address verification API
When PostGrid fits better
Businesses mailing in the United States and Canada that want postal-certified verification and autocomplete under one contract, priced on their annual volume.
- CASS and SERP certified, so US and Canadian addresses are matched to the postal services' own records
- Autocomplete, freeform parsing, city and state from a postal code, and ZIP codes from a city
- A batch endpoint and a Salesforce integration for existing records
- Pricing by quotation against annual volume
When Spaw fits better
Developers who want a written address parsed against its own country's rules and checked against open registers, where a field nobody could evaluate answers null instead of a guess.
- PostGrid answers deliverability from USPS and Canada Post records; Spaw's licensed delivery-point fields answer null, and its Canadian directory carries only the forward sortation area, which the answer says plainly
- PostGrid prices by quotation; Spaw publishes one price per credit, and an address that cannot stand as written costs nothing
- Spaw's confirmation map and changes list say which dataset stood behind each part of the address and what the parser altered, rather than a single Verified, Corrected or Failed status
- Spaw names the register behind every answer and whether its coverage is complete or partial, and a partial register never denies an address
Questions
Does Spaw charge for addresses no register covers?
An address that stands as written costs 1 credit, whether or not a register carried the building. An address that cannot stand costs nothing, whatever the reason, and a repeat within seven days is free. Where no register covers the country, or where the register that answered is one whose coverage is partial and does not carry the address, exists answers null — not evaluated — rather than a verdict, and the not_in_register weight cannot fire. PostGrid does not publish how it bills them.
Can I move an address list from PostGrid to Spaw?
Yes. Upload the CSV in the dashboard or POST it to the bulk endpoint, up to 100,000 addresses a job; Spaw keeps your columns and adds 64 result columns after them (the address as submitted, the answer, the datasets behind it, what the row cost and whether your suppression list answered it), and a country column gives each row its own country. Rows repeating an address already in the list are answered once, cost nothing, and are counted as duplicates.
Is there a free tier?
Every Spaw account receives 100 free credits at the start of each month with no card on file, and unused free credits accumulate. PostGrid offers: "Try for Free. Sign Up for Address Verification API" on the product page; no standing free volume is stated.
Try Spaw on your own list
Free credits every month, no card. Upload a list, keep your columns, and download only the rows you want. See the pricing page for every rule, or the PostGrid alternatives.
PostGrid is a trademark of its owner. Spaw is not affiliated with it. Markdown version: /compare/postgrid.md