Klaviyo Flows One Week Before Black Friday: What Still Works

Every year, the same sequence at the agency: mid-November, a brand writes to us with a half-built Klaviyo account and a simple question. What can we still plug in before Friday?

The honest answer rests on one distinction. Some flows produce revenue as soon as they are activated because they trigger on events that happen continuously. Others need history, tracking already in place or a queue of contacts already built, and one week out they will not catch up on anything.

This article sorts the two categories, and above all it lists the settings that make a flow activated in a hurry fail. Because a live flow that is badly configured during the BFCM weekend costs more than a missing flow.

The rule that decides everything: a live flow does not catch anyone up

Before choosing what to activate, you need to understand what happens the moment you switch a message to live.

Klaviyo's documentation is explicit: setting a message live means that new individuals entering the flow will be queued to receive it (Klaviyo, setting a flow live). Profiles that triggered the event before activation are not included.

In operational terms: an abandoned cart flow activated on Friday at 9 a.m. will reach none of the carts left on Thursday evening. The counter starts from zero.

There is a catch-up mechanism, adding past profiles (formerly back-population), but its reach is not unlimited. Klaviyo states that how far back it reaches depends on the length of the flow (adding past profiles documentation). A short flow catches up on little. And the mechanism does not apply everywhere: on a back in stock flow, the documentation states it has no effect.

Keep this in mind before reading on: one week out, you are not building history, you are capturing a stream. Flows that trigger often win, the others wait for January.

What is still worth activating one week out

1. Abandoned cart, if it does not already exist

This is the one flow that justifies pushing everything else aside. It triggers several times a day on a running account, so it produces revenue from the first day of promotional traffic.

The minimal setup Klaviyo recommends:

• Started Checkout trigger
• first message 2 to 4 hours after the trigger
• 2 to 3 messages in total across the sequence
• buyer exclusion filter: Placed Order zero times since starting this flow

These four parameters come straight from Klaviyo's abandoned cart documentation. The exclusion filter is not optional: without it, you chase people who have just paid, right in the middle of the order peak. That is the surest way to push complaints up at the worst possible time.

One week out, do not try to build a five-branch flow. Two clean emails, an exclusion filter, a clear subject line. If the account already has an abandonment flow in place, go and check the four scenarios detailed in our article on Klaviyo abandonment flows instead, and fix the one that is missing.

2. The welcome flow, short version

BFCM generates a spike in sign-ups: welcome pop-up, pre-sale capture, promo alert forms. Each of those subscribers enters the welcome flow immediately after opting in. The flow needs no history to work.

One week out, a welcome flow with two or three emails is more than enough. The first email must carry the offer, not a 400-word brand story. You will refine the full sequence in January, based on our welcome flow method.

Point of attention: if you are connecting a new pop-up at the same time, check that the form feeds the list that triggers the flow. It is the most frequent mistake we come across in express audits.

3. Post-purchase, in its simplest version

A post-purchase flow activated one week out triggers on every order of the weekend. Guaranteed volume. An enriched confirmation email, a usage-tips or cross-sell email a few days later, and you already have what you need to prepare the second order in December.

The benefit is twofold: this flow works during the peak, and it keeps working afterwards, when campaigns calm down. Our guide to the Klaviyo post-purchase flow details the variants, but one week out the two-email version is the right answer.

4. Browse abandonment, only if tracking is already active

This flow triggers on the Viewed Product metric, which assumes onsite tracking is already in place and sending events (browse abandonment documentation). If you first have to install the tracking, it is not a job for the final week: by the time events come through and you validate the data, Black Friday is over.

Simple test before deciding: open the Viewed Product metric in the account. If it is populated and consistent with traffic, you can activate. Otherwise, let it go for this year.

If you activate, Klaviyo recommends adding a delay of at least one hour before the first message. In a period when visitors compare a lot, that delay avoids emailing someone who is still browsing. The full conditions are covered in our article on Klaviyo browse abandonment.

What to give up on activating one week out

Back in stock

This is the clearest case. The flow triggers on the Subscribed to Back in Stock metric and adding past profiles has no effect on it. In other words: everyone who signed up for a restock alert before your activation will receive nothing.

Second limit to know before plugging it in urgently: after the first message, Klaviyo cannot re-check inventory before sending a second message (back in stock documentation). On a weekend when stock moves every hour, that means emails pushing a product that is already out of stock again. Bad moment for that kind of mistake.

Back in stock is an excellent flow. It gets built in December, with time to test the reminder logic.

Winback and sunset

These flows rest on long inactivity windows. Activated one week out, they will reach almost nobody over the weekend, and the few profiles concerned are exactly the ones you should not solicit just before a sending peak. Our full method on winback and sunset flows remains a January project.

Rebuilding existing flows

Modifying a flow that is running during BFCM week is a risky operation, for a precise technical reason detailed in the next section.

The five settings that make a flow activated in a hurry fail

Smart Sending can skip your flow messages

Smart Sending prevents sending to a contact who was recently solicited. The default window for email is 16 hours, for SMS and push 24 hours, and these windows are independent (Smart Sending documentation).

In normal times, it is a useful protection. During a BFCM weekend when you send several campaigns a day, it becomes a silent filter: a contact who receives your morning campaign may never receive their abandoned cart email in the afternoon.

The decision is a trade-off, not a rule. On a high-value transactional flow like abandoned cart, many operators disable Smart Sending during the peak and turn it back on afterwards. On more editorial flows, keeping it on avoids overheating. What matters: that it is a conscious choice, flow by flow, and not a discovery on Monday morning while reading the stats.

Check the setting on every flow you activate. Klaviyo states that Smart Sending is enabled in many pre-built flows, without publishing the exact list: so it is something to check manually, not to assume.

Trigger filters do not clean the queue already built

A technical point that surprises many CRM managers. On a metric-triggered flow, trigger filters are only evaluated at entry into the flow, while profile filters are re-evaluated before each action (flow filters documentation).

Consequence one week out: if you add a trigger filter to a flow that is already running, contacts already in the queue are not re-filtered. They continue their journey with the old logic. If you want to exclude profiles from the queue in progress, you need a profile filter, not a trigger filter.

That is exactly why retouching an existing flow in a hurry is more dangerous than creating a new one: you end up with two populations following two different logics inside the same flow.

Changing a time delay does not reschedule contacts already scheduled

Same family of trap. Contacts are scheduled step by step, and changing a delay does not reschedule those already scheduled on the current step (time delays documentation).

If you move a delay from 24 hours to 4 hours on Wednesday evening thinking you are speeding up your sequence for Friday, contacts already waiting will still go out on the old delay. The new setting only concerns those who arrive afterwards.

Make your timing adjustments early, or not at all.

SMS quiet hours pause the whole journey, not just the SMS

On omnichannel flows, this is the most expensive trap of the weekend. Klaviyo's SMS quiet hours are by default before 8 a.m. and after 9 p.m. An SMS caught in that window waits for the next sending slot, and during that wait the contact pauses their entire journey: they do not move on to the split, the delay or the email that follow (quiet hours documentation).

On an email plus SMS abandoned cart flow, a cart abandoned at 10 p.m. on Friday can block the whole reminder sequence until the next morning. If your offer expires overnight, the message arrives after the battle.

Two options: take the SMS out of the flow's critical path during the weekend, or build the sequence so that the email never depends on an SMS step. The channel-by-channel trade-off is detailed in our article SMS or email: which message deserves which channel.

Deliverability cannot be fixed one week out, but it can be monitored

A flow activated in a hurry adds volume to an infrastructure that is already about to absorb a campaign peak. The official thresholds to know:

Above 5,000 messages a day to Gmail, Google requires SPF and DKIM, DMARC, valid DNS records, TLS and one-click unsubscribe. If one of these is missing one week out, it is the absolute priority, ahead of any new flow. The configuration details are in our SPF, DKIM and DMARC guide, and the complaint rate requirements in the Google and Yahoo sender requirements.

On ramping up volume before the peak, many figures circulate (daily increase ratios, 30-day or 60-day engagement windows). We do not repeat them here: the official pages we opened do not publish them. What is published and verifiable is the set of thresholds in the table above.

The compliance point, not to be skipped even in a hurry

In France, prospecting by email requires prior consent. There is an exception when the person is already a customer and the prospecting concerns similar products or services (CNIL, commercial prospecting by email). This applies to companies operating in France.

Two implications for a last-minute activation:

• even under the customer exception, the ability to object must be offered simply and free of charge at collection and with each send. A flow set up quickly with an approximate unsubscribe link puts you in breach.
• how this exception applies to a Black Friday offer on a product category the customer has never bought is not settled by the CNIL page. When in doubt about a segment, the cautious position is to stay with opted-in contacts.

If you are reopening dormant lists to inflate volume before the peak, reread our GDPR email marketing checklist before pressing send.

The order of execution over the last seven days

Here is how we sequence this kind of project at the agency when a brand arrives late.

D-7 and D-6: foundations

• check SPF, DKIM and DMARC, plus one-click unsubscribe
• open Postmaster Tools and look at the current complaint rate
• check that the Viewed Product metric is coming through, to decide on browse abandonment
• list the flows already live and their Smart Sending state

D-5 and D-4: activations

• create or fix the abandoned cart flow (Started Checkout, first message 2 to 4 hours after, buyer exclusion filter)
• create the short welcome flow if missing
• create the two-email post-purchase flow
• activate browse abandonment if and only if tracking is validated, with a delay of at least one hour

D-3 and D-2: fine-tuning and tests

• decide on Smart Sending flow by flow and document the decision
• take SMS steps out of the critical path of transactional flows
• send a test email on every flow, on at least three email clients
• freeze time delay changes

D-1: freeze

No more changes to existing flows. The traps described above (trigger filters not re-evaluated, delays not rescheduled) mean a last-minute correction creates more disorder than it resolves. If something is wrong at D-1, the right answer is often to cut the message concerned rather than retouch it.

For the campaign plan that sits on top of these flows, our day-by-day BFCM send calendar gives the full framework, and the segments to prepare are listed in BFCM: 9 Klaviyo segments.

What the final week teaches you for next year

An account that arrives one week out with three missing flows has an organisation problem, not a Klaviyo problem. The list of the seven flows that must be running before Black Friday exists, it is stable from one year to the next, and it gets built in September: we detailed it in the 7 Klaviyo flows that must run before Black Friday.

What plays out in the final week is triage. You activate what captures immediate flow, you set aside what needs history, and you spend the rest of the time on the invisible settings that decide whether your emails really go out.

If you want an outside look at an account before the peak, that is exactly the kind of express audit our Klaviyo agency does.

FAQ

Does a flow activated one week out catch up on abandoned carts from previous days?

No. Setting a message live only queues new entrants into the flow. To reach earlier profiles, you have to go through adding past profiles, whose reach depends on the length of the flow.

Should I disable Smart Sending during Black Friday?

It is a trade-off to make flow by flow. The default window is 16 hours for email and 24 hours for SMS and push. On a transactional flow like abandoned cart, leaving it active during a week of closely spaced campaigns can skip messages to contacts who were already solicited.

Can I activate a back in stock flow one week out?

Technically yes, but it will catch up on no earlier subscriber: adding past profiles has no effect on this type of flow. Klaviyo also cannot re-check stock before sending a second message, which is risky on a weekend when stockouts follow one another.

What happens if I change a delay in a flow that is already running?

Contacts already scheduled on the current step are not rescheduled. Only contacts who enter after the change follow the new delay. That is the main reason to freeze changes at D-1.

Which deliverability thresholds should I watch before the peak?

The complaint rate must stay under 0.10% in Postmaster Tools according to Google, and never reach 0.30%. Yahoo asks you to stay under 0.3%. Above 5,000 messages a day to Gmail, Google's stricter requirements apply: SPF and DKIM, DMARC, valid DNS, TLS and one-click unsubscribe.

Need an express review of your flows before the weekend? Talk to the Deliver team.