How to Improve Email Deliverability? (Essential Preorder app)

What inboxes reward (content signals)

Clarity + specificity: real people, real details (order #, dates, names).
Low spaminess: plain language, minimal hype, no tricks.
Consistency: the links, brand, and “From” identity match.

Do this (content only)

Write honest subjects (45 to 55 characters).
Open with context in line 1: who you are + why they’re getting this.
Include unique facts: order number, product, ship date/timezone, amount/deposit—filters love specifics.
Use your own domain in links (e.g., links.essential-apps.com/...), and keep link text honest (“View order”, not “Click here!!!”).
One clear CTA max. Multiple CTAs look promotional and spammy.
Trim the word count: say it in ~80–180 words for transactional notices.
Ask for a light-weight interaction (reply, confirm, view order) — engagement helps placement.

Avoid (these tank placement)

Clickbait subjects: “URGENT!!!”, “RE: your account” (when it isn’t), “LAST CHANCE!!!”
ALL CAPS, $$$, emojis spammed, excess punctuation!!!
“Free,” “100% guaranteed,” “risk-free,” “act now,” “winner,” etc. (especially in subject).
URL shorteners (bit.ly, tinyurl) and mismatched link text vs destination.
Image-only emails or giant hero images (>150–200KB each) with little text.
Walls of boilerplate, legalese up top, or tracking gibberish in the first lines.
Using noreply@ (hurts engagement) or telling users not to reply.
Mixing promo copy into transactional emails (can reclassify to Promotions/Spam).

What you can change in Essential Preorder emails

The app sends three customer emails: the preorder confirmation, the shipping update and the back in stock alert. You edit their subject, header, description, button and footer in the app. Layout, plain-text version and the sending domain are handled for you.

Placeholders the app understands (single curly braces, nothing else works):

{order} and {orderName} in the preorder confirmation and shipping update emails.
{product} and {link} in the back in stock emails.

Where to edit: Preorder → Settings → Notifications for the two preorder emails (see Preorder emails), and the campaign’s Email tab for back in stock (see Enable Back in Stock notifications).

Subject line examples

Good

Preorder confirmation: Your preorder {orderName} is confirmed
Shipping update: Delivery update for order {order}
Back in stock: {product} is back in stock

Avoid

IMPORTANT MESSAGE OPEN NOW
Last chance for your preorder!!!

Description text examples

Preorder confirmation: Thanks for your preorder. Order {orderName} contains preorder items. We will ship them as soon as they arrive and email you when they are on the way. Reply to this email if anything looks off.

Shipping update: A quick update on order {order}: the preorder items are running later than planned. We are working to get them to you as soon as possible. Reply to this email with any questions.

Back in stock: Good news: {product} is available again. Stock is limited, so order soon.

Keep each under about 80 words, one link or button, and write the specific reason the customer is getting it in the first line.

Quick pre-send checklist

First 2 lines make sense alone (that’s what Gmail/Outlook preview).
1–3 links, all to your domain; no shorteners.
≤1 small image, with alt text; email still clear with images off.
Plain-text version present, links expanded (no tracking gibberish in view).
No ALL CAPS or hype words in the subject.
For promos: unsubscribe is visible; for transactional: explain why they got it.