A signal is an observable event that suggests a company or person may buy now: a visit to your pricing page, a job change, a hiring spree, a funding round, research on a topic, engagement with a competitor's post. The signals layer detects these and hands them to the Sequencing & sending engine, usually via Clay, a CRM or a webhook.
The finding: signals do not just make emails better, they change how many you send. A team that emails only accounts showing intent sends tens or hundreds of emails a day, not thousands — which changes what it needs from a sending tool (see Volume math: what 10k and 100k emails a day cost). And the cheapest, most viral signal products — person-level website visitor ID — work only in the US.
The categories
| Signal type | What it detects | Example vendors | Price point (as of date) |
|---|---|---|---|
| Website visitor ID (person) | Named individuals visiting your site | RB2B, Warmly, Vector | RB2B $0–199/mo (Oct 2026); Warmly from $10k/yr (Oct 2026) |
| Website visitor ID (company) | Companies by IP | RB2B, Common Room, Warmly, Clay (Growth) | Bundled in most |
| Third-party research intent | Topics a company is researching across publisher networks | Bombora (resold in Warmly, Common Room), G2 Buyer Intent | Unpublished |
| Job changes / champions | Past users or buyers moving companies | UserGems, Clay, Unify | UserGems $40k–150k/yr (Overloop, Aug 2026) |
| Hiring, funding, tech changes | Company events | Warmly add-on, Clay, Unify | Warmly GTM Signals $10k/yr add-on |
| Social and community | Engagement with posts, communities, GitHub | Common Room, Trigify (closing) | Common Room Starter $20,400/yr (Landbase, May 2026) |
| Ad-audience signals | Contact-level audiences and account scoring | Vector | Starter $36,000/yr (Oct 2026) |
Bombora and G2 Buyer Intent do not publish prices. No pricing was verified for either.
The vendors that matter
RB2B turned person-level visitor ID into a self-serve product. As of October 2026 it offers 150 free "resolutions" a month, then $79, $149 and $199 plans, overage at $0.25–0.45 per resolution. Person-level identification is labelled "US only"; company-level works globally. It claims 15–20% person-level coverage, 35–45% with premium resolution. It pushes to Clay, HubSpot, Salesforce, Apollo, Slack and webhooks. A ProductLed teardown pinned the weakness: "Nobody wants '150 visitors identified'" — users still have to filter and write the outreach.
Warmly packages visitor ID with AI chat and an "AI Inbound Autopilot". Plans run $10,000, $20,000 and $30,000 a year (October 2026), with a $10,000 GTM Signals add-on that includes Bombora research intent, hiring and funding data.
Common Room aggregates website, community and product signals; its Starter plan is $20,400 a year with 6 Bombora intent topics per a competitor's May 2026 write-up.
Vector sells contact-level ad audiences and 30+ signals from $36,000 a year, positioned against 6sense and Demandbase.
Unify and Clay fold signals into the workflow: Unify now sells signal-based outbound from a free tier and $20–60/seat; Clay puts job-change signals on Launch and web intent on Growth.
Trigify, which turned LinkedIn engagement into prospect lists for $40–199/month, is shutting down: its team announced on 23 September 2026 that it is "joining HubSpot", access ends 22 October 2026, and customer data does not move to HubSpot.
Consolidation is under way at both ends. HubSpot absorbed Trigify's team; Clay and Unify bundle signals into workflows; Warmly bundles them into AI agents. Standalone signal tools at $40–200 a month are being squeezed between free tiers and platform bundles.
How signals change the economics of outbound
Spray-and-pray outbound is a volume game: many domains, many inboxes, thousands of sends a day, a low single-digit reply rate (published averages run 0.45–3.7% depending on the denominator; see Reply benchmarks) and a constant fight with Google and Yahoo sender rules. Signal-based outbound runs on different numbers:
| Spray | Signal-triggered | |
|---|---|---|
| Daily sends per company | Thousands | Tens to low hundreds |
| Inboxes and domains needed | Dozens to hundreds | A handful, often the rep's own |
| Copy | Templates + variables | Written per trigger ("you visited pricing", "new VP Sales") |
| Timing | Batch | Within hours of the event |
| Cost driver | Sending infrastructure | Data and signals |
| Risk | Spam complaints, domain burn | Privacy and "creepiness" |
The step-one effect supports the case: Instantly's 2026 benchmark found 58% of replies come from the first email, so getting the first touch relevant and timely matters more than a long sequence.
No independent dataset comparing reply rates of signal-triggered vs list-based outbound was found. Vendors claim large uplifts — a Landbase competitor page cites "4–7x higher conversion" (Landbase) — but none publishes a method. Overloop's August 2026 roundup recommends testing it yourself: twenty manual messages referencing the signal, measured against your normal baseline.
The money moves accordingly. In a spray model the sequencer and inbox vendors (Inbox & domain infrastructure) capture spend. In a signal model, spend shifts to data: a team might pay $10k–36k a year for Warmly or Vector and very little for sending.
The European problem
Person-level website identification depends on matching cookies and device graphs to identities — data that is largely unavailable or unlawful to use without consent in the EU. RB2B restricts person-level ID to the US. Under GDPR and ePrivacy and Germany's UWG (see Germany), identifying a named visitor and emailing them unprompted is high-risk. Data provenance is also a platform risk: LinkedIn banned Artisan for about two weeks in December 2025 over data brokers that had scraped LinkedIn.
What remains usable in the EU with lower risk: company-level website visits, public company events (funding, hiring, leadership changes), engagement on your own content, product-usage signals for your own users, and consented first-party data. See Data sourcing law.
No legal opinion on person-level visitor ID under German law was reviewed for this page; the law pages carry that analysis.
What this means for an entrant
- Design for triggers, not lists. Accept signals by webhook (RB2B, Clay, CRM, product events), start a one-person sequence within minutes, and write copy per trigger. Volume sequencers built around CSV uploads and inbox rotation are awkward at this.
- Price for low volume, high value. A signal-led team sends 50 emails a day; per-contact or per-inbox pricing built for spray does not fit. Consider per-seat or per-active-sequence pricing.
- Own the EU-safe signal set. Company-level intent, public company events and first-party engagement, packaged with a compliance story, is something US vendors are structurally bad at selling to German buyers.
- Pick up Trigify's orphans. Social-engagement-to-sequence at under $200/month lost its specialist on 22 October 2026.
- Do not build a data business. Bombora, UserGems and Clay own the datasets; integrate them and win on what happens after the signal.