Stop spraying emails at job titles. Target prospects showing buying signals right now.
Rees Bayba
Founder, Astra GTM
TL;DR
Signal-based outbound is the practice of targeting prospects based on observable buying signals -- actions, events, or changes that suggest a company is likely to buy your product right now. Instead of blasting every VP of Marketing at a 200-500 employee SaaS company, you reach the ones who just posted a job for the role your product replaces, lost their head of demand gen, or started evaluating your competitor on G2.
Traditional outbound starts with firmographics: industry, company size, revenue, title. You build a list of everyone who fits, then email them all. Signal-based outbound adds a timing layer. You still filter by firmographics, but you only contact companies showing evidence that they need your product now. The difference is massive. Firmographic targeting tells you who could buy. Signals tell you who is likely buying.
| Dimension | Firmographic targeting | Signal-based targeting |
|---|---|---|
| Selection criteria | Industry, size, revenue, title | Firmographics + active buying signals |
| Timing | Whenever the list is built | When the signal fires |
| Personalization basis | Company description, role | The specific signal event |
| Typical reply rate | 1-3% | 5-11% |
| List size | Large (thousands) | Smaller, higher quality (hundreds) |
| Refresh cadence | Quarterly or ad-hoc | Continuous -- new signals daily |
Based on 23M+ emails sent. Alex Vacca (ColdIQ) documented 54 intent signals that consistently produce these rates, compared to ~3% for untargeted firmographic lists.
Not all signals carry equal weight. A funding round is a strong timing signal -- the company has new capital and pressure to deploy it. A G2 review is a strong intent signal -- someone is actively evaluating tools. The best campaigns stack multiple signals to confirm timing before reaching out.
| Signal type | Where to find it | What it indicates | Urgency |
|---|---|---|---|
| Hiring intent | LinkedIn, Indeed, company careers page | Building a function your product supports | High |
| Funding round | Crunchbase, PitchBook, press releases | Capital to spend, pressure to grow | High |
| Tech stack change | BuiltWith, Wappalyzer, SimilarTech | Replacing or adding tools in your category | High |
| Executive change | LinkedIn Sales Nav, press releases | New leader brings new tools and vendors | Medium-High |
| Competitive product usage | BuiltWith, G2 reviews, job postings | Using a competitor -- potential displacement | Medium |
| G2/Capterra reviews | G2 Buyer Intent, Capterra | Actively evaluating solutions in your category | Very High |
| Event sponsorship | Event websites, LinkedIn posts | Investing in the problem area you solve | Medium |
| Job postings mentioning pain point | Indeed, LinkedIn, Greenhouse boards | The job description describes your product's value prop | High |
| Website visitor ID | RB2B, Warmly, Clearbit Reveal | Anonymous visitor from target account on your site | Very High |
The signal detection stack has matured significantly since 2024. Clay sits at the center for most teams -- it connects to dozens of data providers and lets you build automated signal monitors. But Clay alone is not enough. You need data sources feeding it.
The workflow is different from batch-and-blast. Instead of building a big list once, you build a pipeline that continuously surfaces new signal-matched accounts. Each signal becomes a campaign trigger with its own copy angle.
Signal-based targeting is not always necessary. If your TAM is small (under 500 accounts), you should contact all of them regardless of signals -- you cannot afford to wait for timing triggers. If your product has universal urgency (compliance deadlines, regulatory changes), firmographics alone produce strong reply rates because the timing signal is external and applies to everyone. Signals add the most value when your TAM is large, your product is nice-to-have rather than must-have, and timing determines whether a prospect is receptive.
Signal-based campaigns trade volume for precision. You will contact fewer people, but more of them will respond. A firmographic campaign might email 2,000 people at a 2% reply rate for 40 replies. A signal-based campaign might email 400 people at 8% for 32 replies. Fewer sends, similar output, much lower risk of domain reputation damage, and higher quality conversations because every reply comes from someone with active need.
Alex Vacca (ColdIQ) catalogued 54 distinct buying signals across hiring, funding, tech stack, leadership, and community engagement categories. The taxonomy is the starting point for any signal-based program.
How many signals should I track at once?
Start with 2-3. Hiring intent and tech stack changes are the highest-converting and easiest to detect. Add more signals after you validate these. Tracking 10+ signals before you have a working campaign for any of them spreads your effort too thin.
Do I need Bombora or G2 Buyer Intent, or can I use free signals?
You can start with free signals. LinkedIn job changes, company career pages, BuiltWith's free tier, and Crunchbase funding alerts cost nothing. Paid intent data (Bombora, G2) adds topic-level precision, but many teams run strong signal-based campaigns without it. Start free, add paid data when you have proven the approach works.
How quickly should I act on a signal?
Within 1-2 weeks for high-urgency signals (funding rounds, executive hires). Within a month for medium signals (job postings, event sponsorship). Stale signals are worse than no signals -- if someone raised a round 6 months ago, referencing it feels lazy. Automate your pipeline so new signals trigger outreach within days.
Can signal-based outbound work for SMB sales?
Yes, but the signal sources differ. SMBs rarely appear in Bombora or G2. Instead, track local signals: new business filings, Google My Business changes, Yelp reviews mentioning growth pains, job posts on Indeed. The principle is the same -- reach them when something changes.
What's the difference between intent data and buying signals?
Intent data is a subset of buying signals. Intent data specifically measures content consumption -- what topics a company is researching online (Bombora tracks this via a co-op of B2B publisher sites). Buying signals are broader: they include intent data plus organizational changes, hiring patterns, tech stack shifts, and competitive behavior. Intent data tells you what they are reading. Buying signals tell you what they are doing.
How do I avoid false positives with signals?
Stack signals. A single signal can mislead -- a company might post a job they never fill, or browse G2 out of curiosity. Two or more signals at the same company within 30 days dramatically increase confidence. A funding round plus a relevant job posting is much stronger than either alone. Build your scoring model to weight signal combinations, not individual triggers.
We implement these systems end-to-end. First sends within 14 days.