Where do good cold email leads come from?
Good cold email leads come from a reason first and a database second. Start with people or companies who did something recently that connects to what you sell, then look up the contact. A 2024 Indie Hackers guide to first customers by cold email puts it plainly: the best lead sources "will always be those that haven't been contacted a lot in the past."
| Source | Why it is good | Cost | Effort per lead |
|---|---|---|---|
| Public posts asking for a tool or complaining about one (LinkedIn, X, Reddit) | Named person, their own words, dated | Free by hand | High |
| Job ads for the work you automate | Suggests a budget and a priority | Free | Medium |
| US funding filings (SEC Form D) | Public on SEC EDGAR, dated, and due within 15 days of the first sale | Free | Medium |
| Companies using a tool you replace or plug into | Clear fit and a reason to write | Paid tech-stack tools | Low |
| Contact databases (Apollo, ZoomInfo) | Fast filters by title, size, industry | Free tier, then paid | Low, but everyone else has the same rows |
On funding: the SEC's Form D page says a company must file within 15 days after the first sale of securities in an exempt offering. Our guide to finding startups that just raised and what to say to them covers how to search those filings.
Databases are a fair place to start for names and titles. Apollo's site advertises 240M contacts and 30M companies (checked 24 October 2026). The catch is that every other sender can run the same filters on the same rows.
What makes a cold email lead good quality?
A good lead passes four checks: the company fits, the person can decide or strongly influence the purchase, there is a reason to write that is less than about 30 days old, and the email address verifies. Miss one and the lead belongs in a later batch, not this one.
| Check | Keep the lead if | Drop or park it if |
|---|---|---|
| Fit | Industry, size and type match the customers you can serve today | "Could maybe use it someday" |
| Decision-maker | Owns the budget or the problem (founder, head of the team) | Intern, student, recruiter, or a role with no say |
| Recent reason | A post, job ad, funding round or role change you can name | Only a title match from a database |
| Verified email | "Valid" from a verifier | Invalid, disposable or unknown; accept-all handled with care (see below) |
A list that passes all four is small. That is the point. A list of 100 people with a named reason gives you 100 different first lines. A list of 5,000 title matches gives you one template and a spam folder.
Copy this sheet layout before you start. One row per person:
- Name, title, company, company size
- Signal: what they did, in one line ("posted that month-end close takes 4 days")
- Signal link and date
- Email and verification status
- First line: written from the signal
- Keep? Yes only if all four checks pass
Why do scraped and bought lists hurt you?
Scraped lists hurt in two ways: more bounces and more spam reports, and both damage the domain you send from. Google's email sender guidelines (checked 24 October 2026) say to keep the spam rate in Postmaster Tools below 0.10% and avoid ever reaching 0.30%. In numbers, 0.30% of 1,000 emails delivered to Gmail is 3 spam reports, and 0.10% is 1. The same page says that if messages from your domain are frequently reported as spam, future messages are more likely to be marked as spam.
Bounces are the other half. Hunter, the email finder, published a guide to accept-all addresses (4 November 2025, updated 16 December 2025, no test date given). It sent the same campaign to 100 accept-all addresses and 100 valid ones: 27% of the accept-all group bounced, against 1% of the valid group. That is a small test run by a vendor, so treat it as a warning sign rather than a benchmark. Hunter also says 38% of email domains were accept-all in its analysis of 2,572 addresses.
Volume-first methods make both problems worse. One 2023 Indie Hackers guide suggests scraping the followers of niche accounts with 5k to 50k followers to build a list running to tens of thousands of people. Those people share an interest. Most of them have no reason to hear from you this month. If you are tempted to buy a list instead, read our breakdown of what happens when you send to a bought lead list.
What do cold emailers on Reddit say about lead sources?
Across three threads, the advice repeats: databases are a starting point, verification comes before sending, and several commenters favour leads that come with a reason to write.
- Apollo plus verification is the default stack. In an r/coldemail thread from February 2026 on where people get leads, 22 of the 46 comments the archive returned (removed ones excluded) mention Apollo, and 15 of those also mention verifying addresses or bounce rates. Several are vendors promoting their own tools, so read it as a picture of habits. One commenter's view: "Apollo is saturated now, everyone scraped it."
- Signals beat lists, but not for everyone. In an r/coldemail thread from October 2025 asking for real intent leads, replies point to job postings, Reddit complaints and competitor reviews. One high-volume sender disagreed, saying the only intent signal they count is a purchase from them.
- Narrow the target before hunting for more leads. In an r/SaaS thread from January 2026, a founder looking for a first few customers asked where to find leads. At least five of the 33 replies the archive returned told them to narrow the target to a specific niche or ideal customer first, and two replies suggested pitching companies that are hiring for the manual work the product replaces.
These are individual practitioners' reports, not studies. The useful part is how often the same advice repeats across separate threads.
How to build a 100-lead list in one week
Write one sentence about who you sell to
Industry, company size, the role that feels the problem, and the event that makes it urgent. "Finance leads at 20 to 200 person SaaS companies who just raised" works. "SMBs" does not.
List five reasons to write
For example: asked for a tool, complained about a competitor, hiring for the role, just raised, new in the job. Each one becomes a search you run every day.
Collect 20 people a day from signals
Search posts, job boards and filings first. Use a database only to fill in titles and company details for people you already found.
Find and verify each email
Send only to addresses marked valid. Our guide to finding a decision-maker's work email for free covers pattern guessing and verification.
Write the first line from the signal
The signal column becomes your opener. Our cold email templates give you the rest of the message.
Twenty a day for five days is 100 leads, each with a reason. Send to those before you add more.
How should you handle each email verification result?
Send to valid addresses, drop invalid and disposable ones, and treat accept-all and unknown results as risky. Hunter's help page on verification statuses defines each result:
| Status | What Hunter says it means | What to do |
|---|---|---|
| Valid | The address is active and can receive email | Send |
| Accept-all | The domain reports every address as valid, so the verifier can't confirm this one | Send only with a high confidence score, and keep these a small share of each send |
| Unknown or blocked | The server blocked or greylisted the check | Retry later, or reach the person on LinkedIn |
| Invalid | Failed the checks; doesn't exist or can't receive email | Drop |
| Disposable | A temporary address | Drop |
Hunter's accept-all guide suggests treating addresses with a confidence score of 85 to 100% as valid, and keeping accept-all addresses to around 2 to 5% of a campaign.
If you would rather not build the list by hand, Siela's AI SDR scores each lead hot, warm or cold with a one-line reason, finds and verifies each person's work email, and emails only deliverable addresses. The first email is your own template with each person's name, company and title filled in, sent from your Gmail at up to 150 a day per mailbox, 2 to 5 minutes apart.
Frequently asked questions
Is Apollo good enough for cold email leads?
Apollo is a reasonable place to find names, titles and company details, and its site advertises 240M contacts and 30M companies. The weakness is that every other sender can pull the same rows. Practitioners in a February 2026 r/coldemail thread mostly paired Apollo with a separate verification step before sending, and two commenters said its leads had become saturated.
How many leads do I need to start cold emailing?
Start with about 100 leads that each have a recent, named reason to write, such as a post, a job ad or a funding round. That is enough to test one offer and one message. Collecting 20 a day takes a week. Send to those, read the replies, and only then decide whether to widen the list.
Should I email accept-all addresses?
Carefully. Hunter says an accept-all domain reports every address as valid, so verifiers cannot confirm the mailbox. In Hunter's own 100-versus-100 test, published in November 2025, 27% of accept-all addresses bounced against 1% of valid ones. Hunter suggests sending only to those with a high confidence score and keeping them to 2 to 5% of a campaign.
What columns should a cold email lead sheet have?
Use one row per person: name, title, company and company size; the signal in one line, with its link and date; the email and its verification status; a first line written from the signal; and a keep column. Mark a lead keep only if it passes all four checks: fit, a decision-maker, a reason under about 30 days old, and a verified email.
Can I use SEC Form D filings as a lead source?
Yes, for US companies that raise money in exempt offerings. The SEC says a company must file Form D within 15 days after the first sale of securities in the offering. The filings are public, so they give you a fresh list of funded companies and a dated reason to write. Check each company still fits your ideal customer before you add it, since a filing alone says nothing about need.
Sources
- Indie Hackers: How to get your first 10 customers with cold email (28 Feb 2024)
- Indie Hackers: How to find good quality leads to cold email (9 Feb 2023)
- SEC: Filing a Form D notice (13 Jun 2024, updated 17 Mar 2026)
- Apollo: Pricing (checked 24 Oct 2026)
- Google Workspace Admin Help: Email sender guidelines (checked 24 Oct 2026)
- Hunter: Accept-all (catch-all) email addresses (4 Nov 2025, updated 16 Dec 2025)
- Hunter Help Center: What are the possible verification statuses for an email? (checked 24 Oct 2026)
- Reddit r/coldemail: where do you get your inboxes and leads for your cold email campaigns? (Feb 2026)
- Reddit r/coldemail: How do you find real intent leads for cold email? (Oct 2025)
- Reddit r/SaaS: Tips in B2B SaaS selling, best places to find high quality leads? (Jan 2026)
- SEC EDGAR: Latest filings, form type D (checked 24 Oct 2026)