Email Deliverability for Ecommerce: Staying Out of Spam

You can write the best cart abandonment email in the world, but if it lands in spam, it's worth nothing. Deliverability is the foundation that everything else depends on.

Ecommerce stores face unique deliverability challenges. You're sending high volumes, mixing transactional and marketing emails, ramping up during promotions, and constantly adding new subscribers. Each of these can cause problems if you're not careful.

Here's how to keep your emails landing in the inbox.

Why Deliverability Matters More Than You Think

Most ecommerce stores obsess over open rates, click rates, and conversion rates. But all of those metrics are downstream of deliverability. If 20% of your emails never reach the inbox, you're losing 20% of your potential email revenue before you've even started.

The compounding cost: Poor deliverability doesn't just affect individual emails. It affects your sender reputation, which makes future emails more likely to hit spam, which further damages your reputation. It's a downward spiral that gets harder to fix the longer it continues.

The hidden revenue loss: If your list has 50,000 subscribers and you have a 15% inbox placement issue, that's 7,500 people who never see your emails. If your average revenue per email is $0.50, that's $3,750 in lost revenue per campaign. Over a year of weekly sends, that's nearly $200,000.

For a comprehensive guide that covers deliverability principles across all business types, see our email deliverability guide for 2026.

Ecommerce Deliverability Risk Table

Risk	Why ecommerce stores hit it	Prevention
Sudden volume spikes	Promotions, BFCM, holiday sales, and flash launches	Warm volume gradually before peak periods
Low-quality checkout emails	Guest checkout, typos, and weak consent	Validate signups and suppress non-engagers quickly
Image-heavy campaigns	Product grids and large hero banners	Add real text, alt text, and compressed hosted images
Discount-heavy language	Frequent sale campaigns	Use specific but calm subject lines and avoid spammy stacking
Old inactive subscribers	Lists grow faster than they are cleaned	Suppress long-term non-openers before major campaigns

The Basics: Authentication

Before anything else, make sure your email authentication is properly set up. This is non-negotiable. We have a complete walkthrough in our SPF, DKIM, and DMARC setup guide, but here's the overview.

SPF (Sender Policy Framework): Tells email providers which servers are allowed to send email on behalf of your domain. Your email platform should provide the DNS record to add. Without SPF, any server could claim to send email from your domain, which is a red flag for spam filters.

DKIM (DomainKeys Identified Mail): Adds a digital signature to your emails that proves they haven't been tampered with in transit. Think of it as a wax seal on a letter. If the seal is broken, the recipient knows something went wrong.

DMARC (Domain-based Message Authentication, Reporting, and Conformance): Tells email providers what to do with emails that fail SPF or DKIM checks. It's the policy layer that says "if an email claims to be from my domain but fails authentication, quarantine it or reject it."

If these aren't set up, you're at a huge disadvantage from the start. Most email platforms walk you through this during setup. Sequenzy handles deliverability setup as part of onboarding to make sure your authentication is right from day one.

Check your setup: Use tools like Mail Tester (mail-tester.com) or MXToolbox to verify everything is configured correctly. Run these checks every few months. DNS records can sometimes get accidentally deleted during website migrations or domain changes.

BIMI (Brand Indicators for Message Identification): This is a newer standard that lets you display your brand logo next to your emails in the inbox. It requires DMARC at enforcement level (quarantine or reject). While not strictly necessary for deliverability, it boosts brand recognition and trust, which improves open rates. If you're already set up with DMARC enforcement, BIMI is worth implementing.

List Hygiene

This is where most ecommerce stores go wrong. Your list grows through checkouts, popups, and signups. Not all of those contacts are good.

Remove hard bounces immediately. A hard bounce means the email address doesn't exist. Keep sending to it and email providers will penalize you. Most email platforms handle this automatically, but double-check that yours does.

Suppress long-term non-openers. If someone hasn't opened an email in 6 months, stop sending to them (or reduce to once a month at most). They're either not interested or your emails are going to their spam folder, and continuing to send makes the problem worse.

Watch for spam traps. Old, recycled email addresses sometimes become spam traps. They look like real addresses but exist solely to catch senders with poor list hygiene. The best defense is regular list cleaning. There are two types:

• Pristine spam traps: Email addresses that never belonged to a real person. They get on your list through list purchases or scraping. Never buy email lists.
• Recycled spam traps: Abandoned email addresses that email providers have repurposed. They get on your list when you keep sending to addresses that haven't engaged in years.

Validate new signups. Use double opt-in or at minimum an email validation service to catch typos and fake addresses before they enter your list. Common typos like "gmial.com" or "yaho.com" are easy to catch with validation. Bot signups are harder but can be filtered with CAPTCHA and honeypot fields.

Clean before major campaigns. Before Black Friday, holiday sales, or any high-volume sending period, clean your list. Remove bounces, suppress non-openers, and validate questionable addresses. This is especially important for Black Friday campaigns where you'll be sending at higher volume than usual.

Regular maintenance schedule:

• Weekly: Review and remove hard bounces
• Monthly: Check complaint rates and investigate spikes
• Quarterly: Suppress 6-month non-openers, validate questionable addresses
• Before major campaigns: Full list cleaning pass

List Hygiene Schedule Table

Frequency	Task	Healthy target
Weekly	Remove hard bounces and obvious invalid addresses	Bounce rate stays below 2%
Monthly	Review complaint spikes by campaign	Complaint rate stays below 0.1%
Quarterly	Suppress or reduce 6-month non-openers	Engagement signals improve
Before major sale	Clean list and validate risky imports	Peak sends go only to healthy audiences
After platform migration	Recheck authentication and warm engaged segments first	Reputation rebuilds without shocks

Sending Patterns

How you send matters as much as what you send.

Be consistent. If you normally send 2 emails per week, don't suddenly send 5 per day. Email providers track your sending patterns and flag sudden spikes as suspicious. Consistency builds sender reputation over time.

Warm up gradually. When you move to a new email platform, start with your most engaged subscribers and gradually increase volume over 2-4 weeks. Don't blast your full list on day one. A typical warm-up schedule looks like:

• Week 1: 500-1,000 most engaged subscribers
• Week 2: 2,000-5,000 subscribers
• Week 3: 10,000-25,000 subscribers
• Week 4: Full list

Separate transactional and marketing. Use different sending domains or subdomains for transactional emails (order confirmations, shipping notifications) and marketing emails (campaigns, promotions). This way, if your marketing emails hit spam issues, your transactional emails aren't affected. Your order confirmations and shipping notifications are too important to risk.

Watch your bounce rate. Keep it under 2% per campaign. Consistently higher bounce rates signal poor list quality. If a single campaign bounces at 5%+, investigate immediately. You may have imported bad data or your list needs cleaning.

Monitor complaint rates. If more than 0.1% of recipients mark your email as spam, you have a problem. This is the threshold that Gmail and other providers use. At 0.3%+, you're in serious trouble and need to take immediate action.

Throttle large sends. If you're sending to 100,000+ subscribers, consider spreading the send over several hours rather than blasting everyone at once. This reduces the spike in sending volume and gives you time to catch problems early (if the first 10% have high bounce rates, you can pause before the rest goes out).

Ecommerce-Specific Deliverability Issues

High-Volume Promotional Periods

During Black Friday, holiday season, and major sales, you'll send more emails than usual. Email providers know this is a high-spam period and are extra vigilant.

What to do:

• Ramp up volume gradually in the weeks before. If you normally send 2 emails per week, go to 3 two weeks before, then 4 the week before.
• Prioritize your most engaged segments for the earliest and most important sends
• Send your least engaged segment last (or skip them entirely)
• Monitor deliverability metrics in real time during your sale
• Have a fallback plan if deliverability drops mid-campaign

Pre-BFCM deliverability checklist:

1. Clean your list 2-3 weeks before
2. Run a re-engagement campaign to warm up lapsing subscribers
3. Verify authentication records are intact
4. Check domain reputation in Google Postmaster Tools
5. Send a test campaign to a seed list across multiple providers
6. Gradually increase send volume in the weeks leading up

Checkout Opt-In Quality

Many ecommerce stores collect email addresses at checkout with a pre-checked marketing opt-in box. This gives you volume but not quality. People often check out as guests with throwaway emails or don't realize they opted in.

Better approaches:

• Make the opt-in checkbox unchecked by default (and it's legally required in some jurisdictions)
• Set clear expectations: "Get exclusive offers and new product alerts"
• Send a welcome email immediately to confirm engagement
• Suppress contacts who don't engage with any of the first 5 emails
• Use a separate welcome series that quickly identifies engaged vs. disengaged subscribers

The checkout email problem: About 15-20% of email addresses collected at checkout are low quality. They may be valid addresses that the person checks rarely, temporary email addresses, or addresses with typos. The key is to identify these quickly and suppress them before they damage your sender reputation.

Product Image Emails

Ecommerce emails tend to be image-heavy (product photos, lifestyle shots, banners). This can cause deliverability issues.

Best practices:

• Include real text content alongside images (not just images)
• Use alt text for all images (helps accessibility and displays when images don't load)
• Don't use a single large image as your entire email
• Keep your image-to-text ratio reasonable (60/40 is a good target)
• Compress images so they load quickly
• Host images on a reliable CDN that won't go down during high traffic
• Avoid embedding images. Always use hosted images with links.

Why image-only emails are dangerous: Some spam filters analyze the ratio of images to text. An email that's 100% images with no readable text looks suspicious. Additionally, many email clients block images by default on first load. If your email is all images with no alt text, the recipient sees a blank email and is more likely to mark it as spam.

Coupon and Discount Language

Certain words and phrases trigger spam filters more often. Be careful with:

• ALL CAPS in subject lines
• Excessive exclamation marks!!!
• Words like "FREE," "GUARANTEED," "ACT NOW"
• Dollar signs in subject lines ($$$)
• Phrases like "limited time offer" in all caps
• Multiple punctuation marks (???, !!!)

You can still use these words, just don't pile them all into one email. "50% off everything this weekend" is fine. "FREE!!! BIGGEST SALE EVER!!! ACT NOW!!!! $$$" is not.

Subject line best practices for deliverability:

• Keep subject lines under 50 characters
• Use sentence case, not ALL CAPS
• Limit special characters and punctuation
• Avoid deceptive subject lines ("Re:" or "Fwd:" when it's not a reply)
• Personalize where possible (personalized subject lines have lower spam rates)

Promotion Subject Line Table

Risky pattern	Safer alternative	Why
"FREE!!! BIGGEST SALE EVER!!!"	"40% off this weekend"	Specific without shouting
"ACT NOW $$$"	"Ends tonight: winter sale"	Urgent but readable
Fake reply prefix	"Your early access is open"	Avoids deceptive formatting
Vague hype	"Best sellers under $50"	Gives a concrete reason to open
Long mobile-truncated line	"Cyber Monday: 30% off"	Keeps the offer visible in inboxes

If you want to optimize your subject lines, our guide on A/B testing email subject lines covers how to test effectively while keeping deliverability in mind.

Engagement Metrics That Affect Deliverability

Email providers like Gmail use engagement signals to decide whether to put your email in the inbox, promotions tab, or spam folder.

Positive signals:

• Opens and clicks
• Replies (one of the strongest positive signals)
• Moving an email from promotions to primary inbox
• Adding your address to contacts
• Forwarding your email to others
• Spending time reading your email (dwell time)

Negative signals:

• Deleting without opening
• Marking as spam (the strongest negative signal)
• Never opening your emails
• Immediately archiving or deleting
• Mass-deleting emails from your sender

This is why segmentation matters so much for deliverability. Sending to engaged subscribers keeps your positive signals high. Sending to disengaged subscribers drags them down.

The Gmail promotions tab reality: Many ecommerce emails land in the promotions tab, not the primary inbox. This isn't necessarily bad. Gmail users who shop online know to check their promotions tab. Your open rates from the promotions tab might be lower than primary inbox, but the people who do open are there intentionally and tend to convert at higher rates.

How to improve engagement signals:

• Segment your list and send relevant content to each segment
• Make your emails worth opening (valuable content, not just sales pitches)
• Encourage replies by asking questions or inviting feedback
• Send at consistent times so subscribers know when to expect you
• Remove disengaged subscribers proactively, don't wait until they hurt your metrics

Domain Reputation vs. IP Reputation

Understanding the difference helps you diagnose deliverability problems.

IP reputation: The reputation of the specific server (IP address) sending your email. If you're on a shared IP (common with most email platforms), other senders on that IP can affect your deliverability. If you're on a dedicated IP, the reputation is entirely yours to build and maintain.

Domain reputation: The reputation of your sending domain. This has become more important than IP reputation in recent years, especially with Gmail. Your domain reputation follows you even if you change email platforms.

For most ecommerce stores: Domain reputation matters more. Focus on:

• Consistent sending patterns from your domain
• Good engagement metrics for emails from your domain
• Proper authentication (SPF, DKIM, DMARC) for your domain
• Not using your main domain for high-risk sends (use a subdomain)

When to consider a dedicated IP: If you're sending more than 100,000 emails per month consistently, a dedicated IP gives you more control. Below that volume, it's hard to build enough positive reputation on a dedicated IP, and a shared IP with a reputable platform is usually better.

What to Do When You Hit Spam Issues

If your deliverability suddenly drops, here's a systematic approach to fixing it.

Step 1: Check your authentication. Make sure SPF, DKIM, and DMARC are all passing. Use Google Postmaster Tools to check your domain reputation. Authentication failures are the most common and most fixable cause of deliverability drops.

Step 2: Check your bounce rate. A spike in bounces often precedes deliverability problems. Remove bounced addresses immediately. If you recently imported a list or haven't cleaned in a while, this is likely the culprit.

Step 3: Check for spam complaints. Review your complaint rate in your email platform's dashboard. If it's above 0.1%, something in your recent emails upset people. Look at which specific email triggered the complaints. Was it a subject line issue? Content issue? Did you email a segment that wasn't expecting to hear from you?

Step 4: Reduce your sending to engaged-only. For 2-4 weeks, only send to subscribers who have opened or clicked in the last 30 days. This rebuilds your positive engagement signals and gives your reputation time to recover.

Step 5: Gradually re-add segments. Once your deliverability recovers, slowly bring back less-engaged segments. Add 10-20% more of your list each week. Monitor metrics at each step. If deliverability dips again when you add a segment, that segment needs more cleaning.

Step 6: Investigate root causes. Did you recently change your email content, increase frequency, or add a large batch of new subscribers? Identify what changed and fix it. Common triggers include:

• Switching email platforms without proper warm-up
• Importing a purchased or scraped list
• Dramatically increasing send frequency
• Sending to a very old list that hasn't been cleaned
• A specific campaign with misleading subject lines

Step 7: Monitor the recovery. Use Google Postmaster Tools to track your domain reputation over the following weeks. It typically takes 2-4 weeks to see reputation improvements reflected in inbox placement.

Deliverability Across Email Providers

Different email providers handle filtering differently. What works for Gmail might not work for Yahoo or Outlook.

Gmail: Heavily weighted toward engagement signals and domain reputation. If your emails get consistently opened and clicked by Gmail users, you'll have good inbox placement. Gmail's promotions tab is a separate consideration from spam.

Outlook/Hotmail: Relies more on content filtering and sender reputation. Outlook's SmartScreen filter can be aggressive with promotional content. Consistent sending patterns matter more here.

Yahoo/AOL: Uses engagement signals similar to Gmail but with different thresholds. Yahoo tends to be more aggressive with new senders.

Apple Mail: Doesn't do its own spam filtering in the same way. It relies on the underlying email provider (iCloud, Gmail, etc.). However, Apple's Mail Privacy Protection can inflate your open rates since it pre-loads tracking pixels.

The Apple Mail Privacy Protection impact: Since Apple introduced Mail Privacy Protection, open rates for Apple Mail users are artificially inflated. This means you can't rely on open rates alone to measure engagement. Click rates and purchase behavior are now more reliable indicators of true engagement.

Tools for Monitoring Deliverability

Google Postmaster Tools: Free. Shows your domain reputation, spam rate, and authentication status for Gmail specifically. Every ecommerce store should have this set up. Check it weekly.

Your email platform's dashboard: Most platforms show bounce rates, complaint rates, and deliverability scores. Check these after every campaign, not just monthly.

Seed testing: Services like Mail Tester or GlockApps send your email to test inboxes across providers and tell you where it lands. Run seed tests before major campaigns to catch issues early.

Inbox placement monitoring: Premium services that continuously monitor your inbox placement across providers. Worth the investment if email drives more than 20% of your revenue.

Blacklist monitoring: Check if your sending IP or domain is on any email blacklists. MXToolbox provides free blacklist checks. Being on a blacklist can instantly tank your deliverability.

Getting Started

If you haven't thought about deliverability before:

1. Verify your SPF, DKIM, and DMARC records are set up correctly
2. Set up Google Postmaster Tools for your domain
3. Remove anyone who hasn't opened an email in 6+ months from your active list
4. Check your bounce rate and complaint rate for recent campaigns
5. Make sure transactional and marketing emails use separate sending identities
6. Run a seed test with Mail Tester to see where your emails land
7. Set up a monthly deliverability review cadence

Good deliverability isn't something you set up once and forget. It requires ongoing attention. But the payoff is huge. If your emails actually reach the inbox, everything else in your email marketing works better. Your cart recovery emails, your retention sequences, your promotional campaigns, all of them depend on deliverability as the foundation.

Frequently Asked Questions

What's a good deliverability rate for ecommerce?

Aim for 95%+ inbox placement. That means 95% or more of your emails reach the inbox (not spam or promotions). Anything below 90% indicates a problem that needs immediate attention. Note that inbox placement is different from delivery rate. You can have a 99% delivery rate (emails accepted by the server) but only 80% inbox placement (emails that actually reach the inbox vs. spam folder).

How do I know if my emails are going to spam?

Several indicators: declining open rates over time, sudden drops in click rates, customers telling you they didn't receive your email, and Google Postmaster Tools showing increased spam rates. Seed testing tools give you the most direct answer by sending your email to test inboxes across providers and reporting where it lands.

Should I use a shared or dedicated IP address?

For most ecommerce stores sending under 100,000 emails per month, a shared IP with a reputable email platform is fine and often preferable. You benefit from the collective reputation of all senders on that IP. If you're sending 100,000+ per month consistently and want full control over your reputation, a dedicated IP makes sense. But you'll need to warm it up properly, which takes 2-4 weeks.

How often should I clean my email list?

Clean continuously, not just periodically. Remove hard bounces immediately after every send. Suppress 6-month non-openers quarterly. Do a full list clean before major campaigns like Black Friday. If you're adding subscribers at a high rate (through popups, checkout opt-ins, ads), validate new addresses in real time before they enter your list.

Does the Gmail promotions tab count as a deliverability problem?

Not really. The promotions tab is not the spam folder. Gmail users who shop online regularly check their promotions tab. Your emails being in promotions tab is expected for marketing emails and shouldn't be treated as a deliverability failure. Focus on spam placement, not promotions tab placement. That said, if you want more emails in the primary tab, encourage replies and add personal touches to your emails.

What should I do if I'm on an email blacklist?

First, identify which blacklist and why. Most blacklists have a lookup and delisting process. Fix the underlying issue (usually sending to spam traps or high complaint rates) before requesting delisting, or you'll end up back on the list. Common blacklists include Spamhaus, Barracuda, and SORBS. MXToolbox can check all major blacklists at once.

How does email deliverability affect my email revenue?

Directly and significantly. If 10% of your emails hit spam instead of the inbox, you're losing roughly 10% of your email revenue. For a store generating $20,000/month from email, that's $2,000/month or $24,000/year in lost revenue. Improving deliverability is one of the highest-ROI activities in email marketing. For more on measuring email revenue accurately, see our revenue attribution guide.

Can I send marketing and transactional emails from the same domain?

You can, but you shouldn't use the same sending identity. Use subdomains to separate them (e.g., mail.yourstore.com for marketing, notifications.yourstore.com for transactional). This way, if your marketing emails encounter deliverability issues, your order confirmations and shipping notifications are protected. Your customers need to receive those transactional emails regardless of your marketing email reputation.