# ProspectAPIs, free, POST /v1/watchlists: Company funding API

> A watchlist is a saved set of funding filters plus an https webhook. Each new funding round that matches is POSTed to your webhook, signed, so you hear about a raise without polling, and you pay only for the records a watchlist delivers.

ProspectAPIs's company funding API on its Free plan. It costs $0.00 per 1,000 companies. It returns 6 of the 13 key fields we check: Round, Amount, Date, Investors, Sources, Headquarters.
We rank 114 plans by price. [Signalbase's €99 monthly plan](https://datacircle.dev/company-funding-apis/signalbase/99-monthly-pro-post-csv-enrichment/llms.txt) costs the least per 1,000 companies: $0.056.
[The Swarm](https://datacircle.dev/company-funding-apis/the-swarm/500-monthly/llms.txt), [Skrapp](https://datacircle.dev/company-funding-apis/skrapp/349-monthly-enterprise-50k-get-api-v3-companies-enrich/llms.txt) and [Parsers VC](https://datacircle.dev/company-funding-apis/parsers-vc/249-monthly-scale-get-startups-id-fundingrounds/llms.txt) are the best company funding API providers in our benchmark.

- This page: https://datacircle.dev/company-funding-apis/prospectapis/free-post-v1-watchlists
- [Best company funding API in 2026](https://datacircle.dev/best-company-funding-api.txt)
- Get it: https://prospectapis.com/pricing
- Request: `POST https://api.prospectapis.com/v1/watchlists`
- API key: with the plan, on https://prospectapis.com/pricing
- Its API docs: https://prospectapis.com/docs/reference/create-watchlist
- Sold by: ProspectAPIs (https://prospectapis.com)
- Checked: 2026-10-26

## In the answer

- Completeness: 46%
- Round: ✓
- Amount: ✓
- Date: ✓
- Investors: ✓
- Sources: ✓
- Headquarters: ✓

## Price

- $ per 1,000 companies: $0.00
- Per: result
- Billing: free

## Aggregators

- Aggregators: none

## Charges

- Also pays for: from the same budget: Search funding rounds · Read one funding round · Start a research brief · Verify email addresses · Clean a list · Start a verification job · Find an email address

## Not found

- $ per 1,000: $0.00

## In their words

- Their pitch: A watchlist is a saved set of funding filters plus an https webhook. Each new funding round that matches is POSTed to your webhook, signed, so you hear about a raise without polling, and you pay only for the records a watchlist delivers.

## Data

- Freshness: 2 hours
- Keep data: no limit
- Use data: Check anything that matters before you rely on it, and do not use the service as the only basis for a decision with legal or similar effect on a person. You may use what the API returns inside your own products and workflows. You may not resell or republish the data as a substantially similar dataset or API. [...] Use of the service must follow the acceptable use policy. [...] This policy sets the limits on how the service and its output may be used. [...] Use it for: Researching companies and the people who publicly represent them in a business role. Preparing for sales calls and writing outreach that is relevant to the recipient. Account research, territory planning and enriching business records with funding history. Do not use it to: Profile private individuals, or research anyone outside a business context. Harass, stalk, threaten or discriminate against anyone. Send messages that break anti-spam or marketing consent laws where the recipient is. Make decisions about employment, credit, insurance or housing for an individual. Resell or republish the data as a substantially similar dataset or API. Share API keys between unrelated parties, or create accounts to multiply free records. Probe, overload or work around the rate limits, billing or security of the service. Send the research API inputs you have no right to share, such as confidential third-party data in context.

## Plan

- Pay: $0
- You get: $1
- Enough for: 50 results, once
- Expires: never

## Rate limit

- Per second: 1

## Speed

- Answer: by webhook

## The call

- You send: name, filters, webhook_url
- Method: POST
- Path: /v1/watchlists

## About the plan

- Plan: Free
- Who can get it: anyone, one account per person or company

## The 21 fields the plan's answer can hold

record ID, company name, company domain, event class, round label, round stage, amount (USD), original amount, currency, announced date, investors, lead investors, headquarters location, headquarters country code, source URL, attributes, updated at, event type, delivery ID, watchlist ID, delivered at

## ProspectAPIs's plans (5)

- [ProspectAPIs, free, POST /v1/watchlists](https://datacircle.dev/company-funding-apis/prospectapis/free-post-v1-watchlists/llms.txt): $0.00 per 1,000, 46% complete, 2 hours
- [ProspectAPIs, top-up from $10, Credit pack, any amount from $10 to $10,000, POST /v1/watchlists](https://datacircle.dev/company-funding-apis/prospectapis/top-up-from-10-credit-pack-any-amount-from-10-to-10000-post-v1-watchlists/llms.txt): $20.00 per 1,000, 46% complete, 2 hours
- [ProspectAPIs, top-up from $100, Top-up of $100 or more, +25% bonus credit, POST /v1/watchlists](https://datacircle.dev/company-funding-apis/prospectapis/top-up-from-100-top-up-of-100-or-more-25-bonus-credit-post-v1-watchlists/llms.txt): $16.00 per 1,000, 46% complete, 2 hours
- [ProspectAPIs, top-up from $500, Top-up of $500 or more, +60% bonus credit, POST /v1/watchlists](https://datacircle.dev/company-funding-apis/prospectapis/top-up-from-500-top-up-of-500-or-more-60-bonus-credit-post-v1-watchlists/llms.txt): $12.50 per 1,000, 46% complete, 2 hours
- [ProspectAPIs, top-up from $2,000, Top-up of $2,000 or more, +120% bonus credit, POST /v1/watchlists](https://datacircle.dev/company-funding-apis/prospectapis/top-up-from-2000-top-up-of-2000-or-more-120-bonus-credit-post-v1-watchlists/llms.txt): $9.091 per 1,000, 46% complete, 2 hours

## ProspectAPIs's calls for this API (3)

- `POST /v1/watchlists`: [ProspectAPIs, free, POST /v1/watchlists](https://datacircle.dev/company-funding-apis/prospectapis/free-post-v1-watchlists/llms.txt)
- `GET /v1/funding/:id`: [ProspectAPIs, free, GET /v1/funding/:id](https://datacircle.dev/company-funding-apis/prospectapis/free-get-v1-funding-id/llms.txt)
- `GET /v1/funding`: [ProspectAPIs, free, GET /v1/funding](https://datacircle.dev/company-funding-apis/prospectapis/free-get-v1-funding/llms.txt)

## ProspectAPIs's APIs (4)

- [ProspectAPIs: company enrichment API pricing, 5 plans](https://datacircle.dev/company-enrichment-apis/prospectapis/free/llms.txt)
- [ProspectAPIs: email finder API pricing, 5 plans](https://datacircle.dev/find-email-apis/prospectapis/free/llms.txt)
- [ProspectAPIs: email verification API pricing, 5 plans, POST /v1/email/clean](https://datacircle.dev/validate-email-apis/prospectapis/free-free-post-v1-email-clean/llms.txt)
- [ProspectAPIs: email verification API pricing, 5 plans, POST /v1/email/verify/jobs](https://datacircle.dev/validate-email-apis/prospectapis/free-free-post-v1-email-verify-jobs/llms.txt)
- [ProspectAPIs: email verification API pricing, 5 plans, POST /v1/email/verify, Verify email addresses](https://datacircle.dev/validate-email-apis/prospectapis/free-free-post-v1-email-verify-verify-email-addresses/llms.txt)
- [ProspectAPIs: email verification API pricing, 5 plans, POST /v1/email/verify, Verify email addresses, quick check](https://datacircle.dev/validate-email-apis/prospectapis/free-free-post-v1-email-verify-verify-email-addresses-quick-check/llms.txt)
- [ProspectAPIs: company funding API pricing, 5 plans, POST /v1/watchlists](https://datacircle.dev/company-funding-apis/prospectapis/free-post-v1-watchlists/llms.txt)

## ProspectAPIs: company funding API alternatives

- [NeuralVerge, $1,000 monthly, Enterprise, POST /functions/v1/run-tracxn-companies-funding](https://datacircle.dev/company-funding-apis/neuralverge/1000-monthly/llms.txt): $5.00 per 1,000, 31% complete, live
- [Autobound, $1,299 pack](https://datacircle.dev/company-funding-apis/autobound/1299-pack/llms.txt): $9.00 per 1,000, 54% complete, 1 day
- [Olostep, $99 monthly](https://datacircle.dev/company-funding-apis/olostep/99-monthly/llms.txt): $9.90 per 1,000, 38% complete, live
- [NinjaPear, $22,788 yearly](https://datacircle.dev/company-funding-apis/ninjapear/22788-yearly/llms.txt): $15.429 per 1,000, 31% complete, live

## Sources

From each provider's own pricing page and docs, and from what providers tell us. We read this row from these pages on 2026-10-26.

- https://prospectapis.com
- https://prospectapis.com/about
- https://prospectapis.com/acceptable-use
- https://prospectapis.com/docs/rate-limits
- https://prospectapis.com/docs/reference/create-watchlist
- https://prospectapis.com/docs/watchlists
- https://prospectapis.com/pricing
- https://prospectapis.com/terms