Subletter.io — Complete Advertiser Guide

1. Overview

Subletter.io connects advertisers and newsletter publishers across every major industry — from tech and finance to lifestyle and SaaS.

It allows you to promote your product, brand, or newsletter directly inside the inbox of highly engaged readers, with full transparency and performance-based pricing.

Why advertisers love Subletter.io

• Reach verified, high-intent audiences who actually read newsletters.

• Pay only for real results — clicks or subscribers.

• Launch a campaign in minutes, and track every result in real time.

2. Campaign Types

🔹 Click Campaigns

Your ad is placed inside relevant newsletters across Subletter’s verified network.
You only pay when a reader clicks your link.

➡️ Goal: drive qualified traffic to your website, product, or landing page.

🔹 Opt-in Campaigns

Your ad lets readers subscribe to your newsletter in one click, without any form or landing page.
Every subscriber you acquire is a real, verified reader who opted in directly from another trusted newsletter.

➡️ Goal: grow your newsletter with high-quality, engaged subscribers.

Why these subscribers perform better

Readers acquired through other newsletters are already used to engaging with email content.
They trust the publisher recommending you — which creates a transfer of credibility to your brand.

This means:

• higher open rates (often 40%+),

• 2–3× higher click-through rates than social media leads,

• and stronger long-term retention.

3. Creating Your Ad

🖼️ Image Specifications

Your creative appears inside sponsored sections of partner newsletters (footer, mid-content, or dedicated block).
For best rendering on both desktop and mobile:

💡 Tip: Keep it simple — clear logo, concise tagline, and a single visual focus.

✍️ Ad Copy

• Headline: up to 60 characters, focus on the benefit.

  “Get 10,000 qualified subscribers for your newsletter”

• Description: 1–2 short sentences explaining your offer.

  “Promote your brand to readers who already trust top newsletters in your niche.”

• Call-to-action (CTA): direct and actionable.

  “Start Campaign” • “Subscribe Now” • “Get Started”

• Destination link: automatically tracked by Subletter via a redirect
  (https://app.subletter.io/redirect?campaignId=...)

4. Newsletter Targeting

Subletter offers multi-layer targeting to ensure your ad reaches the most relevant readers possible.

🧩 1. Newsletter-level Targeting

You can filter newsletters by:

• Category: e.g., Finance, Tech, SaaS, Startups, Marketing, Health, etc.

• Language: English, French, German, Spanish, Polish, and more.

• Audience region:

  • 🇺🇸 United States

  • 🇬🇧 United Kingdom

  • 🇫🇷 France

  • 🇩🇪 Germany

  • 🇵🇱 Poland

  • 🇪🇺 Europe

  • 🌍 Global

🎯 2. Intra-newsletter Audience Targeting

Even inside a single newsletter, your ad is only shown to subscribers who match your exact filters.

🧠 Example:
If you target English-speaking SaaS readers in Europe, your ad will only be shown to European subscribers who read in English and engage with SaaS-related content, even within global newsletters.

5. Budget & Pricing

💰 CPC (Cost per Click) Model

Subletter.io runs on a performance-based CPC model — you only pay for verified, unique clicks.
Your actual CPC depends on your niche, region, and the newsletters you select.

On average, most performing campaigns see a CPC between $0.70 and $1.20.

🔢 Recommended Budgets

• Minimum: $250 (≈ 80–400 clicks depending on CPC).

• Ideal starting range: $500–$1,000 to collect enough data for optimization.

🎁 Promotional Credits

New advertisers often receive bonus ad credits to kickstart their first campaign.
Example:

Pay $500 → Receive $2,000 in bonus credits → $2,500 total ad balance
At $0.50 CPC, that’s 5,000 qualified clicks.

💌 Opt-in Campaigns (CPA – Cost per Acquisition)

In Opt-in campaigns, you pay only when a real reader subscribes to your newsletter via the one-click “Subscribe” button in your ad.

Example: A $1,000 campaign can generate 800–5,000 new subscribers, depending on niche and geography.

Why Opt-in Subscribers Convert Better

Subscribers acquired through newsletters:

• are already used to engaging with email content,

• trust the creator who recommended your newsletter,

• and voluntarily opt in through a frictionless one-click process.

👉 These subscribers are typically 3–5× more engaged than those acquired through paid social ads.
They open more emails, click more often, and have a higher lifetime value (LTV).

6. Tracking & Reporting

Each campaign comes with a real-time analytics dashboard, including:

• number of clicks or subscribers,

• actual CPC / CPA,

• breakdown by country, language, and newsletter,

• open and conversion rates,

• and budget spend over time.

Data is tracked through Subletter’s infrastructure (Firebase + Postmark) to ensure accurate attribution and de-duplication.

7. Best Practices

✅ Target precisely — fewer, more relevant newsletters outperform broad lists.
✅ Keep visuals clean and readable.
✅ Focus each campaign on a single goal (traffic or subscribers).
✅ Review results every 2–3 days and reallocate budget accordingly.
✅ Test multiple creatives and CTAs.
✅ Use bonus credits to experiment with new segments.
✅ Optimize your landing page or onboarding flow for conversions.

8. Example Setup