Checklist to review an email campaign before sending

Sending mass emails involves operational and reputational risks that can be avoided through a systematic verification process. For small and medium-sized enterprises, establishing a control routine before hitting the send button is the most effective strategy to prevent costly errors, such as broken links, incorrect segmentations, or regulatory non-compliance. This checklist organizes critical reviews into five logical blocks: strategy and audience, content and design, links and navigation, legal compliance, and technical tests.

1. Strategy, audience, and objectives

Before reviewing the design, it is fundamental to validate the campaign logic. A perfectly designed email sent to the wrong audience is an operational failure.

• Single objective: Define one main action (Call to Action or CTA). Ambiguity in options reduces conversion.
• Segmental relevance: Verify that the content matches the behavior and interests of the selected segment. Sending generic messages to specific audiences increases unsubscribes.
• Success criteria: Establish metrics prior to sending. For example, an open rate of 25% – 30% for newsletters or a click-through rate of 3% – 5% for promotional campaigns.
• Schedule and time zone: Confirm the date, time, and, crucially, the time zone of the destination. A configuration error can result in sending at midnight for the target audience.

2. Content, subject, and preview

The text determines the first impression. Clarity and honesty are key to preventing email providers from classifying the message as spam.

• Subject line: It must be honest, specific, and aligned with the content. Avoid "clickbait" or misleading phrases, as inbox providers penalize these practices by reducing deliverability.
• Preview text (Preheader): This field, which displays between 40 and 100 characters additionally, should complement the subject, not repeat it. Ensure it does not contain template remnants like "View in browser" or "Click here if images do not load".
• Personalization: Verify that merge tags, such as [Name], render correctly for all recipients. An error here can display empty text or incorrect data.
• Spelling and grammar: Review all text. Typographical errors erode brand trust.

3. Links, CTAs, and navigation

Broken links are one of the most common and damaging errors. A user who finds a 404 page loses trust in the brand.

• Exhaustive link testing: Click on all links, including the logo, social media icons, footer links, and main buttons.
• UTM parameters: If you use web analytics, confirm that each link includes the correct UTM parameters (source, medium, and campaign) to ensure the accuracy of the subsequent report.
• Correct destination: Ensure that links do not point to test versions (staging), old campaigns, or pages in the wrong language.
• Touch accessibility (Mobile): CTA buttons must be large enough and spaced appropriately to facilitate thumb touch on mobile devices.

4. Design, rendering, and accessibility

Emails are interpreted differently in each email client (Gmail, Outlook, Apple Mail, Yahoo). What looks good in the editor may break in the actual inbox.

• Multi-device testing: Check the design on mobile, desktop, and tablet. The email width should be maintained between 600 and 640 pixels for optimal readability.
• Dark mode: Verify that the design adapts correctly to dark mode, ensuring that text and background contrast is legible.
• Alternative texts (Alt Text): All images must have alternative text. This improves accessibility for screen readers and provides context if the image does not load.
• Safe fonts: Use safe web fonts with appropriate fallbacks to avoid drastic changes in typography depending on the device.

5. Legal compliance and deliverability

Non-compliance with data protection and marketing regulations can result in significant fines and damage the brand's reputation.

• Physical address: Include a valid company postal address in the footer, a legal requirement in many jurisdictions.
• Unsubscribe mechanism: It must be visible, functional, and allow unsubscribing in a single click. Comply with regulations such as GDPR, CAN-SPAM, or CASL according to the territory of your subscribers.
• Consent: Ensure that all recipients have given their explicit consent to receive communications.
• Authentication (SPF/DKIM): Verify that the domain authentication records are correctly configured. This is vital for emails to reach the main inbox and not the spam folder.

6. Final tests and sending

The last control barrier before mass sending.

• Sending to real inboxes: Do not rely solely on the editor preview. Send test emails to real accounts of Gmail, Outlook, Yahoo, and Apple Mail.
• Spam test: Use spam analysis tools to detect words or formats that may trigger security filters.
• Identity review: Confirm that the sender name (From Name) and email address (From Email) are consistent with the brand and subscriber expectations.
• Second pair of eyes: For critical campaigns, require approval from a second team member before scheduling the send. This additional review prevents human errors due to time pressure.