> ## Documentation Index
> Fetch the complete documentation index at: https://deepline.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Email Waterfall

> Find verified work emails by trying multiple providers in sequence. Use it to pilot on a few rows, verify the output, and scale the workflow safely.

Try multiple email providers in cost order, stop at the first valid hit. You only pay for the one that works. Industry benchmarks suggest this gets **better coverage** than using any single provider alone ([Instantly](https://instantly.ai/blog/waterfall-enrichment/)).

## Pick Your Starting Point

Deepline automatically selects the right waterfall based on what data you have:

| You have                                 | Waterfall used                         | Typical cost    |
| ---------------------------------------- | -------------------------------------- | --------------- |
| Name + domain                            | `name_and_domain_to_email_waterfall`   | 0.1-0.4 credits |
| LinkedIn URL + name                      | `person-linkedin-to-email`             | 0.3-0.4 credits |
| LinkedIn URL or name + domain (personal) | `personal_email_waterfall`             | 0.3-0.5 credits |
| Company + role (find contacts)           | `company_to_contact_by_role_waterfall` | 0.2-0.6 credits |

## How It Works

Each waterfall follows the same pattern:

<Steps>
  <Step title="Try cheapest provider first">
    Deepline sends the request to the lowest-cost provider (e.g., Dropleads at
    \~0.3 credits).
  </Step>

  <Step title="Validate the result">
    If the provider returns an email, Deepline checks it's a real address — not
    a catch-all or bounce.
  </Step>

  <Step title="Fall through on miss">
    If the provider fails or returns invalid, Deepline moves to the next
    cheapest provider automatically.
  </Step>

  <Step title="Stop on first valid hit">
    The moment a valid email is found, the waterfall stops. You're only billed
    for providers that ran.
  </Step>
</Steps>

## Single Lookup

In Claude Code, type:

```
/deepline-gtm Find the work email for the VP of Engineering at Ramp (ramp.com)
```

<Accordion title="CLI command">
  ```bash theme={null}
  deepline tools execute name_and_domain_to_email_waterfall \
    --payload '{"first_name":"Jane","last_name":"Smith","domain":"ramp.com"}'
  ```
</Accordion>

## Bulk Enrichment (CSV)

```
/deepline-gtm Run waterfall email enrichment on leads.csv
```

Deepline reads the column headers and picks the right waterfall variant. If your CSV has `first_name`, `last_name`, and `domain` — it uses the `name_and_domain_to_email_waterfall` (which tries free patterns first). If it has `linkedin_url` — it uses the LinkedIn waterfall.

<Accordion title="CLI command">
  ```bash theme={null}
  deepline enrich --input leads.csv --output enriched.csv \
    --with '{"alias":"email","tool":"name_and_domain_to_email_waterfall","payload":{"first_name":"{{first_name}}","last_name":"{{last_name}}","domain":"{{domain}}"}}'
  ```
</Accordion>

## Provider Order

Providers are tried in sequence. The exact chain depends on the waterfall variant, but a typical order:

1. **Dropleads** (0.3 cr)
2. **Hunter** (0.3 cr)
3. **LeadMagic** (0.4 cr)
4. **Deepline Native** (1.0 cr)
5. **Crustdata** (1.2 cr)
6. **PeopleDataLabs** (4.0 cr)

<Tip>
  **BYOK mode:** If you bring your own API keys, waterfall lookups are free —
  you pay providers directly at their rates. In managed mode, a typical lookup
  costs 0.3-0.4 credits (first provider hit). Worst-case if all providers fire:
  up to 7.2 credits.
</Tip>

## Pilot Mode

Always test before running a full file:

```
/deepline-gtm Run waterfall email enrichment on leads.csv — just the first 3 rows
```

Or with the CLI: `--rows 0:1`

## When to Use Each Variant

* **Name + company + domain** — Most common. Use when you have a lead list with company info.
* **LinkedIn URL** — Use when scraping from LinkedIn or when LinkedIn is your primary identifier.
* **Name + domain only** — Use when you don't have the company name, just the website.
* **Email → context** — Reverse enrichment. You have emails, you want person/company data back.
* **Company + role** — Prospecting. Find contacts at target companies by job title.

***

See the auto-generated pages below for exact provider chains, parameters, and per-variant cost breakdowns.