11 Email Signature Mistakes That Make You Look Unprofessional
Your signature is attached to every email you'll send this year. These eleven mistakes quietly undermine it — most take two minutes to fix.
The eleven mistakes
The broken image
Nothing says “didn't check” like a blue question-mark box where your logo should be. Fix: hosted https images, never dragged-in files — full diagnostic here.
The inspirational quote
“Be the change…” below your phone number costs you credibility with every recipient who's seen it mocked. Fix: delete. Your role is the message.
Image-only signatures
One big PNG of your whole signature: unreadable when images are blocked, uncopyable phone number, invisible to screen readers. Fix: real text + hosted images for the visual parts.
Six social icons
Nobody follows your Pinterest from an invoice email. Fix: LinkedIn plus at most one other active, professional profile.
Three phone numbers
Office, mobile, fax, Skype… recipients freeze. Fix: the one number you actually answer, as a tap-to-call link.
The unsized logo
Renders fine on your Mac, arrives billboard-sized on phones. Fix: explicit width/height attributes — size guide.
Comic Sans energy
Decorative fonts either break (most clients don't have them) or work — which is worse. Fix: email-safe stacks: Helvetica, Arial, system fonts.
The novel-length disclaimer
Eight lines of legal boilerplate in bold black reads as paranoia. Fix: if required, style it 11px gray below the signature.
The stale promo banner
“Register for our March webinar!” in July. Fix: rotate banners monthly or remove them — a calendar reminder works.
Different signature on every device
Polished from the Mac, “Sent from my iPhone” from the phone — where you answer the urgent ones. Fix: same signature on both — how.
No signature at all
The other extreme: a bare sign-off makes every new contact google you. Fix: even a minimal name/title/company block beats nothing.
Zero of the eleven, by default
Autograph's templates are built so these mistakes can't happen — sized hosted images, safe fonts, quiet disclaimers, and the same signature on Mac and iPhone.
Download Autograph free See the templatesCommon questions
What's the single most damaging mistake?
Broken images — it's visible, it's on every email, and it signals carelessness. It's also the most fixable (hosted images).
How many of these does the average signature have?
Two or three. The most common combo: dragged-in logo (breaks), a quote, and no phone link.
What does a mistake-free signature look like?
4–7 lines, one accent color, real text, hosted images with explicit sizes, one CTA at most, tiny gray disclaimer if required. See the examples page.