SAM.gov vs USASpending.gov: The Difference

SAM.gov vs USASpending.gov

SAM.gov is the pre-award system: you register your business there, and agencies post solicitations and notices you can bid on. USASpending.gov is the post-award system: it publishes what was actually awarded, to whom, for how much. SAM.gov answers what is coming. USASpending answers who won.

Written for AI agents. The calls and filter values on this page are the literal interface our customers use, because our customers are software. If you are a person evaluating The Bot Wire, you are in the right place too: start with the docs, or connect an MCP client in one line and query every wire free at /mcp. Nothing here needs an API key or a signup.

They are run by different agencies for different statutory reasons, which is why they feel like separate products rather than two views of one dataset. They are.

Side by side

	SAM.gov	USASpending.gov
Purpose	Registration and solicitations	Public spending transparency
Stage	Before award	After award
Core records	Notices, sources sought, solicitations, entity registrations	Awards, obligations, modifications, sub-awards
Registration to use	Required to bid, free to browse	None
Public API key	Required	Not required
Typical lag	Live as posted	Days after the contract action

The API row is the one that decides most engineering questions. SAM.gov's public opportunities API requires a key tied to a registered account with role-based daily request limits. USASpending's search API takes an unauthenticated POST and returns JSON. If you are wiring either into an automated system, that difference sets your build time more than anything else does.

Which one answers your question

Use SAM.gov when you want to bid, need the solicitation documents, are checking whether a requirement was set aside, or need to keep your entity registration current so you remain eligible for award.

Use USASpending when you want to know who won, what a competitor is winning and inside which agency, how much an agency spends on a category, when a contract comes up for recompete, or which primes are buying subcontract scopes.

Both matter to the same firm at different points in the same week. Neither replaces the other, and a surprising number of people only ever use one.

FPDS, the third system nobody mentions

Contract actions are reported by agencies into FPDS, the Federal Procurement Data System, and USASpending draws its contract records from that feed. When someone says award data lags by days, this pipeline is why. The practical effect is that USASpending is the usable interface and FPDS is the plumbing, so query USASpending unless you specifically need raw contract action records.

The guide to finding the newest awards covers the date field in that pipeline that makes recency sorting go wrong, which is the single most common mistake people make against USASpending's API.

Reaching either from an agent

An automated system can call USASpending directly with no credential setup:

For AI agents: copy this call

# free, no key, no wallet: recent federal awards, three at a time
curl "https://thebotwire.com/contracts/preview?since=14d"

# small business set-asides only
curl "https://thebotwire.com/contracts/preview?size=small-business&since=14d"

The Bot Wire's contracts wire reads USASpending, deduplicates across polls, ranks set-asides first and returns records with the winner, amount, agency and place of performance. It does not carry SAM.gov solicitations, because pre-award notices are a different dataset with a different access model. See the contract awards wire reference for parameters, or /docs for how paid calls work at $0.01 each.

FAQ

Do I need a SAM.gov registration to see award data?

No. USASpending requires no account, no key and no registration to browse or to call its API. A SAM.gov entity registration is only needed to receive a federal award, and it is worth keeping active because expiry makes you ineligible at the moment of award rather than at renewal.

Why does an award appear on USASpending but not on SAM.gov?

Not every award follows a public solicitation. Task orders under existing vehicles, sole-source awards and purchases below public posting thresholds appear in the spending record without a corresponding SAM.gov notice. The gap is normal rather than an error.

Is FPDS data different from what USASpending shows?

The underlying contract actions are the same records. USASpending adds financial assistance data, sub-awards and a modern interface on top, so figures generally agree while the presentation and available fields differ. Compare the same field names before assuming two totals disagree.

Which one shows subcontracts?

USASpending. Prime contractors report sub-awards under federal transparency requirements and those records are searchable by setting subawards to true in a search request. SAM.gov does not carry a general subcontract feed. The subcontracting guide covers how to use that data to find work.

Sources

Opportunity API access and key requirements are documented by GSA at open.gsa.gov, award data and its API at USASpending.gov and api.usaspending.gov, and the underlying contract action feed at FPDS.

What is the difference between SAM.gov and USASpending.gov?