Newsletter Sponsor Leads: Find Substack Newsletters That Take Sponsors

Enter your niche. Get a ranked list of Substack newsletters that already sell sponsorships, with proof. Each lead includes the advertise page, sponsored posts, past sponsors, subscribers, engagement, audience fit and a clearly labeled cost-per-send estimate. You also get a business email, but only when the publisher lists one publicly.

Built for brands and startups buying newsletter ads, agencies and media buyers, newsletter ad networks and AI agents that plan sponsorship campaigns.

Just press Start. The default niches return about 12 to 15 sponsor-ready leads in roughly 70 seconds.

Real output (default run on the Apify platform, Oct 15, 2026)

#	Newsletter	Subscribers	Sponsor evidence	Past sponsors	Est. cost per send*
1	The Founders Corner	77,000	Sponsorship page, with a public business email	n/a	$1,540 to $3,850
2	On Brand Magazine	27,000	Sponsored posts	Tracksuit	$540 to $1,350
3	Behind the Craft	154,000	Sponsorships page	n/a	$3,080 to $7,700
4	MKT1 Newsletter (Emily Kramer)	87,000	Sponsored posts	Framer, Profound, Traction Complete	$1,740 to $4,350
5	Because of Marketing	96,000	Sponsored posts	Lions Across Europe, Tracksuit	$1,920 to $4,800
6	Product Growth (Aakash Gupta)	241,000	Sponsored posts	n/a	$4,820 to $12,050

*An estimate, not a quote. It assumes typical newsletter CPMs of $20 to $50 per 1,000 subscribers. Real rates vary, so always confirm with the publisher. If the publisher's advertise page lists prices, they appear in listedPricesOnAdPage.

One full row, shortened:

{
  "rank": 1,
  "leadScore": 60.2,
  "newsletter": "The Founders Corner®",
  "url": "https://www.the-founders-corner.com",
  "takesSponsors": "yes",
  "sponsorLikelihood": 55,
  "advertisePage": "https://www.the-founders-corner.com/p/sponsorship",
  "publicBusinessEmail": "founderscornermedia@gmail.com",
  "contactSource": "publisher's advertise/sponsor page",
  "estimatedCostPerSend": "ESTIMATE $1,540-$3,850 per send (assumes typical $20-$50 CPM on 77,000 subscribers; not a quoted price)",
  "subscribers": 77000,
  "credibilityScore": 64.9,
  "audienceFit": 63,
  "medianEngagementPerPost": 43.5,
  "postsPerWeek": 4.06,
  "niche": "B2B SaaS growth"
}

How sponsor detection works

1. Advertise or sponsor page: we look for a link on the newsletter's homepage and check common paths such as /p/sponsorships and /advertise.
2. Sponsored posts: we read the full text of recent free posts and look for "sponsored by", "presented by", "brought to you by", "today's sponsor", "in partnership with" and "(ad)".
3. Past sponsors: we pull brand names from those sponsor lines, so you can see who already buys placements.

takesSponsors is yes when there's an advertise page, at least 2 sponsored posts or named past sponsors. It's likely when there's one sponsored mention, and not detected otherwise. Turn on Include newsletters with no sponsor evidence to see the rest.

Lead score (0 to 100)

• 45% sponsor likelihood (page, sponsored posts, past sponsors)
• 45% credibility score (subscribers, engagement per post, comment depth, consistency, recency, topic fit)
• 10% audience fit with your niche

Privacy and compliance

• Public data only. No login, and nothing behind a paywall.
• Contact details come only from what the publisher lists publicly: the email on its own advertise or sponsor page, or the support email shown on the publication. We never guess, build or enrich personal email addresses.
• Estimates are always labeled as estimates.

Input

Field	Default	Notes
niches	AI tools for marketers, B2B SaaS growth, creator economy	Your audience's topics. Be specific.
maxLeads	15	Each lead is $0.02
minSubscribers	1,000	Filters out tiny newsletters
includeNotDetected	false	Also return newsletters with no sponsor evidence
postsToScan	6	Recent free posts read in full for each newsletter
candidatePool	18	Newsletters checked per niche

Pricing (pay per event, no subscription)

• $0.20 per run (search started)
• $0.02 per sponsor lead returned

A 15-lead run costs $0.50, and 1,000 leads cost about $20 plus run fees. You only pay for leads that appear in your dataset.

Use with AI agents (MCP and API)

The tool works with the Apify MCP server (mcp.apify.com) and any HTTP client. Example agent prompt: "Find 20 Substack newsletters about personal finance that take sponsors, with at least 10K subscribers, and list their advertise pages." Fields are flat and self-describing, and the SUMMARY record in the key-value store gives a plain-text list.

FAQ

Only Substack? Yes, for now. Substack hosts many of the largest independent newsletters, and its data is public.

Why is a newsletter I know missing? It may not rank in Substack search for your niche, or it may sell sponsorships privately. Try more specific niches or raise candidatePool.

Is the cost estimate a price quote? No. Contact the publisher for real rates.

Support

Open an issue on the Actor's Issues tab. We read every issue and usually reply within 1 to 2 days.