Start at the Sign-up Form
Your welcome series does not start inside the flow builder. It starts on your website with the sign-up form, and getting this wrong undermines everything that follows.
Straight off the bat, you need separate mobile and desktop forms. User behaviour on a phone is fundamentally different from a laptop, and if you do not separate the devices, you will never be able to run a clean A/B test. We always ask for a first name alongside the email address. Personalising the subject line with a first name consistently lifts open rates, provided you do not overdo it.
Use a multi-step form to capture zero-party data on step two. Ask what categories, products, or pain points they are interested in, and save that answer as a custom profile property. That single choice allows us to split people in the automation later and speak directly to what they actually want.
Finally, give them the discount code right there on the success screen of the popup. Some marketers argue this hurts email deliverability because subscribers do not need to open email one immediately. In my books, removing friction to get the first purchase beats a tiny deliverability bump every day of the week.
Setting Up Triggers, Filters, and Suppression Tags
The trigger for this flow is simple: joining your main newsletter list. The flow filters, however, need to be strict.
Add a filter where placed order equals zero times over all time. If someone subscribes during checkout and immediately buys, sending them a 10% discount code five minutes later will only frustrate them. Those buyers belong in a post-purchase flow, not a welcome sequence.
The very first action in the flow should be an Update Profile Property block setting in_welcome_series = yes. We then build a dynamic segment of anyone with that property set to yes and exclude them from all regular campaign sends. You want this flow running without conflicting marketing messages distracting the subscriber. When they finish the flow (or buy something), we flip that property back to no.
Email 1 and 1B: The 12-Hour Window
Email 1 goes out immediately. Deliver exactly what they signed up for with zero fluff. I prefer using a static coupon code with links that auto-apply the discount at checkout to make buying frictionless.
Then comes Email 1B after a 12-hour delay. A 12-hour window sounds unusual, but conversion rates drop off a cliff after the first 12 to 16 hours. If they have not purchased within half a day, you need to step in while your brand is still fresh in their mind.
In Email 1B, consider bumping the discount slightly for non-buyers. Getting product into people's hands is priority number one. Provided your margins and repeat order rates support it, sacrifice a little margin upfront to secure the customer lifetime value.
Capturing Missing Data with Email 1C
Not every subscriber will complete step two of your sign-up form. That is normal. After a 2-day delay, we insert a conditional split asking whether their interest category property is set.
If the answer is no, we send Email 1C. This email replicates the question from the form using clickable buttons with dynamic update property links. When a user clicks a button for a specific category, Klaviyo updates their profile property instantly and redirects them straight to that collection page.
Capturing this zero-party data matters even if your list is tiny. You will rely on these properties later for advanced campaign segmentation and paid advertising audiences.
Category Splits: Personalise What Matters
After a 3-day delay, we branch the flow based on the zero-party data we captured. This is where email marketing actually becomes effective.
We use conditional splits using the 'contains' logic for each key collection. If someone told you they are interested in a specific product line, stop sending them generic overviews. Send them an email highlighting top sellers, benefits, and reviews strictly for that category.
- Category match: Send a tailored email focused on their specific interest and remind them of the active offer.
- No match: Send a clean overview of your brand's core USPs, bestsellers, and a reminder of their discount.
Generic marketing is lazy marketing. Speak directly to what people told you they want.
The Urgency Push and Aggressive Hygiene
The final regular email in the sequence, Email 1E, lands after a 4-day delay. This is your expiry reminder. Use dynamic countdown timers only if your discounts genuinely expire, because faking urgency on static codes is poor practice.
Once the sequence finishes, we update the profile property back to in_welcome_series = no, allowing them back into campaign sends. But there is one final check I always run: a conditional split for anyone who opened emails zero times since starting this flow.
If a subscriber went through the entire welcome series without opening a single email, they are exceptionally unlikely to engage later. We automatically tag them with suppress = true and remove them from our active billing tier. With Klaviyo pricing models, keeping unengaged dead weight on your list is a mistake.
Final Thoughts
A high-performing welcome series is not just a three-part brand introduction. It is an automated engine designed to capture zero-party data, tailor messaging by category, and clean out unengaged contacts before they harm your deliverability. Set these filters and splits up once, and your automation will do the heavy lifting for every new subscriber.
If you want our team to audit your current flows and build out a tailored automation strategy for your store, take a look at our email automation services.
