Ask ten email marketers about short links and you'll get two camps. One says short links tank deliverability and belong nowhere near an email. The other uses them in every campaign and swears the analytics are worth it. Both camps are working from half the picture.

The truth is narrower: some short links hurt deliverability in some contexts, and the difference comes down to domain reputation and where the link appears. Used carelessly, a short link can nudge a borderline email into spam. Used deliberately, short links solve real problems — plain-text emails, SMS-and-email combos, links people will retype, and tracking that survives outside your email service provider's walls. This guide separates the two cases so you can use short links where they help and skip them where they don't.

Why short links have a reputation problem in email

Spam filters evaluate every domain in an email — the sending domain, the reply-to, and every link. Free public shorteners have been abused by spammers for two decades because they hide the real destination. Filters responded by treating heavily-abused shortener domains as a risk signal.

Note what the risk signal actually is: the specific domain's reputation, not "shortness" as a concept. A link is not suspicious because it's short. It's suspicious when it lives on a domain that has recently carried phishing campaigns, or when it hides its destination in a message that already looks borderline. This distinction drives every recommendation that follows.

There's a second, subtler mechanism. Most ESPs (Mailchimp, Klaviyo, Brevo, and the rest) already wrap your links in their own tracking domains to count clicks. If you insert a short link, the chain becomes: ESP tracking domain → shortener domain → destination. Two redirects through two third-party domains is more machinery than most emails need, and it can slow the click experience even when it doesn't trip filters.

When short links help in email — and when they hurt

The decision is contextual. Here's the honest breakdown:

Scenario	Short link?	Why
Standard HTML campaign via an ESP	Usually no	ESP already tracks clicks; hyperlink text hides the URL anyway
Plain-text emails	Yes	The raw URL is visible; a 150-character tagged URL looks terrible and wraps across lines
Cold outreach / sales sequences	Careful	These emails are scrutinized hardest; any reputation-poor domain hurts. Use a trusted or branded domain only
Transactional emails	Rarely	Trust is paramount; show clean full URLs
Email + SMS combined campaigns	Yes	One short link works in both channels and unifies the click data
URLs users may retype or forward	Yes	Short links survive retyping and forwarding; long tagged URLs don't
Print/QR driving to an email signup	Yes	Covered in our QR code marketing guide

The pattern: short links earn their place wherever the URL is visible to the reader or needs to travel across channels. Inside a styled HTML button where nobody sees the href, the case is weaker — though the cross-ESP analytics argument below can still tip it.

Spam filter considerations, practically

If you decide to use short links in email, these are the practices that keep them from becoming a liability:

Never use domains with poor reputations. Some legacy free shortener domains are blocklisted outright by corporate mail gateways. Check any domain you plan to use against major blocklists before your first send.
Don't mix many link domains in one email. An email whose links span four unrelated domains looks assembled by a bot. Keep it to your sending domain plus at most one link domain.
Make the visible text honest. Linking the text "yourcompany.com/pricing" to a different URL underneath is a classic phishing pattern that filters specifically look for. Use descriptive text ("See pricing") or the actual short link as the text.
Warm up gradually. If you switch a large list to short links overnight, engagement dips at scale get noticed. Introduce them in a segment first, compare bounce and spam-complaint rates, then roll out.
Keep the rest of the email clean. Link reputation is one signal among many. Authenticated sending (SPF, DKIM, DMARC), a warmed sending domain, and non-spammy copy give you margin; a shaky sender gets no benefit of the doubt on anything.

Branded domains: the real answer

Almost every deliverability concern above dissolves when the short link lives on a domain associated with your brand. A link like yourbrand.link/spring carries your reputation, not a shared public domain's. Filters see a consistent brand across sender and links. Recipients see a name they recognize, which lifts clicks too — recognizable link domains reliably outperform anonymous ones on click-through.

A branded short domain also insulates you from other people's behavior. On a shared public shortener domain, your links share reputation with every other user's links, including the bad actors. On your own domain, your reputation is yours alone — for better and worse, which is its own incentive to keep your list practices clean.

If you're sending email at any real volume and want short links in the mix, a branded domain isn't a nice-to-have. It's the price of entry. Setup details are in the documentation, and the FAQ covers common domain questions.

Tracking clicks alongside ESP metrics

Your ESP reports opens and clicks. So why add link-level tracking at all? Because ESP metrics have real blind spots:

Bot inflation. Corporate security scanners and Apple's Mail Privacy Protection pre-fetch links and images, inflating opens and sometimes clicks. ESPs filter this imperfectly.
Walled data. ESP clicks live in the ESP. Comparing email against your social campaigns, QR codes, and SMS means exporting from four dashboards with four definitions of a click.
The story ends at the click. ESPs see the click; they don't see the destination context unless you wire up conversion tracking separately.

The clean setup uses both layers. Tag your destination URLs with UTM parameters (utm_source=newsletter&utm_medium=email&utm_campaign=may-promo — conventions in our UTM parameters guide), shorten the tagged URL, and put the short link in the email. Now the ESP reports email-side behavior, the short link gives you a channel-comparable click count with timing and device data, and GA4 attributes downstream conversions. When numbers disagree — and they will — the disagreement itself is information, usually pointing at bot traffic or blocked analytics.

For SMS-adjacent programs this matters double: an SMS link shortener link reused in the email edition of the same campaign gives you a true cross-channel read from a single link's dashboard.

A/B testing CTAs with short links

Because each short link tracks independently, they make a lightweight CTA testing rig — including tests your ESP can't easily run.

Pick one variable. Button copy ("Start free" vs "Create your link"), link placement (hero vs post-scroll), or format (button vs text link). One variable per test, or you learn nothing.
Create one short link per variant, both pointing at the same destination, with utm_content distinguishing them (utm_content=cta-hero vs utm_content=cta-footer).
Split your audience with your ESP's A/B tools, or simply place both variants in the same email if you're testing placement rather than copy.
Read clicks in the link dashboard, conversions in GA4. The variant that wins clicks doesn't always win signups. Judge on the metric that matters.
Run it to reasonable volume. A few hundred clicks per variant before declaring anything. Small samples produce confident nonsense.

The underrated version of this: testing the same CTA across channels. One campaign, one offer, distinct short links for email, Instagram, and SMS. Two weeks later you know your cost per click by channel with no spreadsheet gymnastics.

Frequently asked questions

Do short links automatically send email to spam?

No. Spam placement is scored across many signals — sender authentication, domain reputations, content, list quality, engagement history. A short link on a reputable or branded domain in an otherwise healthy email is a non-event. A link on a blocklisted shortener domain in a borderline email can be the last straw. The domain's reputation is the variable, not the link's length.

Should I shorten links if my ESP already tracks clicks?

For standard HTML campaigns, often not — the href is hidden and the ESP counts clicks. Shorten when the URL is visible (plain text), when the link must work across channels (email + SMS), or when you want click data that lives outside the ESP for cross-channel comparison.

Is a double redirect (ESP tracking + short link) a problem?

It adds a hop, which adds a small delay and a small amount of complexity for filters to inspect. It's rarely fatal, but if the short link's analytics duplicate what the ESP gives you, drop one layer. Keep both only when the short link adds data the ESP can't provide.

What's the single best thing I can do before using short links in email?

Set up a branded short domain. It converts the main deliverability risk (shared domain reputation) into an asset (consistent brand trust), and everything else in this guide gets easier from there.

Closing thoughts

Short links in email aren't good or bad — they're a tool with a right and wrong context. Skip them in standard HTML sends where your ESP already does the work. Reach for them in plain text, cross-channel campaigns, and anywhere a human sees or retypes the URL. Put them on a branded domain, keep the visible text honest, and layer UTMs underneath so every click lands in your analytics correctly attributed. Do that and the deliverability debate stops being scary and starts being a settings checklist. If you're building the broader measurement stack, the link analytics guide is the natural next read.