How long does it typically take to warm up a new client's email list in Klaviyo?

While there's no fixed duration, a typical warming period for a new client's list in Klaviyo is about 2-4 weeks. This allows sufficient time to gradually increase sending volume and build a positive reputation with ISPs, as discussed in our IP warmup strategy guide . The exact timeline depends on the list size, its quality, and the engagement rates you observe during the process.

Which segments should I target first when warming up a new list?

You should start by sending to your most engaged segments, such as recent purchasers or subscribers who have actively interacted with the brand. These contacts are most likely to open and click, which sends positive signals to ISPs. Gradually expand to broader segments as your sender reputation strengthens.

What are the warning signs that my warming strategy is not working?

If you notice high bounce rates, low engagement, or an increase in spam complaints, you should immediately pause your warming efforts. Re-evaluate your list quality, content, and sending frequency. It may be necessary to further clean your list or reduce your sending volume until metrics improve. Our blocklist monitoring page can help identify if your domain has been blacklisted.

Should I start with automated flows or campaigns in Klaviyo for a new client?

For a new client with a completely new email infrastructure, it's best to start with automated flows like welcome series or abandoned cart flows. These typically have higher engagement rates and are less likely to trigger spam filters. Once your reputation is built, you can introduce campaign sends. This differs slightly from warming up after migrating ESPs , where some reputation might carry over.

What is the best practice for warming up a new client's email list in Klaviyo? - Sender reputation - Email deliverability - Knowledge base

Warming up a new client's email list in Klaviyo is a critical step for establishing a strong sender reputation and ensuring high deliverability rates. When you're dealing with a list that hasn't been emailed before, or a brand new Klaviyo account, treating the initial sends with caution is paramount. The goal is to gradually introduce your sending activity to inbox providers, proving that your emails are legitimate and valued by recipients, rather than overwhelming them and being flagged as spam.

Starting a new client's email program on a platform like

Klaviyo requires a strategic approach to warming. This isn't just about sending emails; it's about building trust with internet service providers (ISPs) like Google and Yahoo. They monitor your sending patterns, engagement rates, and how recipients interact with your emails to determine your sender reputation. A poor warming strategy can lead to your emails landing in spam folders or being blocked entirely, undermining your client's marketing efforts from the start.

Preparing your Klaviyo account and list

Before you even think about hitting 'send' on a campaign, the first and most crucial step is to meticulously clean the client's existing email list. An old, unengaged, or improperly sourced list is a recipe for deliverability disaster. Even if the list has loyal customers, it might contain inactive addresses, spam traps, or addresses that will hard bounce, which can severely damage your sender reputation.

List cleaning services can identify and remove these problematic contacts, reducing your bounce rate and improving overall engagement metrics from the get-go. This pre-emptive cleaning significantly mitigates the risk of being placed on a blacklist or blocklist, which can be difficult to recover from. Remember, quality over quantity is key, especially when warming up a new domain or IP.

Once the list is clean, segmenting it is the next logical step. Identify your most engaged subscribers or recent purchasers, as these are the individuals most likely to open and interact with your emails. This initial engagement is vital for building a positive sender reputation. Starting with a smaller, highly engaged segment allows you to establish a strong foundation before gradually expanding your sending volume.

List health considerations

Source verification: Confirm that all contacts on the list are truly opted-in. Unsolicited emails are a leading cause of spam complaints and can lead to emails going to spam.
Engagement data: If historical data exists, segment based on recent opens, clicks, or purchases. These are your most valuable contacts for initial sends.
List age: Be cautious with lists that haven't been emailed in over a year. It's often safer to treat them as cold lists, or even start fresh, due to the higher risk of bounces and spam traps, as explored in our guide on warming up an old email list.

Executing the warming strategy

When you're ready to start sending, begin with automated flows, particularly a welcome series. These flows typically have high engagement rates because recipients have recently opted in or made a purchase, indicating their active interest. This initial engagement builds a positive sending history with ISPs, showing them that your emails are desired and opened by recipients. Klaviyo's support provides useful advice for understanding which warming process to use.

For the first week or two, focus exclusively on these highly engaged segments. Gradually increase your sending volume and expand to slightly less engaged segments over several weeks. A typical warming period can last anywhere from two to four weeks, depending on the size and quality of the list, and your engagement rates. The warming process typically takes around 30 days.

Content during the warming phase should be highly engaging and non-promotional. Think welcome messages, brand stories, or valuable content that encourages opens, clicks, and replies. Avoid aggressive sales pitches that could lead to spam complaints or unsubscribes, as these negative signals are detrimental during the warming period. Ensure the emails are clearly identifiable and include an easy-to-find unsubscribe link.

Sample warming schedule for a new Klaviyo list

Week	Volume focus	Content type	Key metrics to monitor
Week 1	Smallest, most engaged segments (e.g., recent purchasers, last 30-day openers)	Welcome series, brand story, onboarding emails, value-driven content. Low promotional.	High open rates (20%+), high click rates, low bounce rates (<1%), zero spam complaints.
Week 2	Expand to slightly larger, engaged segments (e.g., last 90-day openers, new subscribers)	Continue flows, introduce soft campaigns (e.g., educational content, product features without hard sell).	Maintain strong engagement, monitor for any increases in complaints or bounces. Gradually scale volume.
Week 3-4	Further expand to broader engaged segments, introduce less recent but still active contacts.	Introduce more regular campaign sends, gentle promotional content (e.g., discount for first purchase, limited offers).	Observe consistent engagement. If metrics are stable, you can begin to scale sending to the full list, as discussed in warming up large lists.

Monitoring and optimizing deliverability

Consistent monitoring of your deliverability metrics within Klaviyo, and potentially through external tools, is non-negotiable during the warming phase. Pay close attention to your open rates, click-through rates, bounce rates (both soft and hard bounces), unsubscribe rates, and spam complaint rates. Ideally, you want high engagement and very low negative feedback. Klaviyo provides helpful resources for understanding email deliverability metrics.

If you notice any spikes in bounce rates or complaints, immediately pause your sending and investigate. This might indicate an issue with list quality or content. Addressing these issues promptly is crucial to prevent further damage to your sender reputation. Being placed on a blocklist or blacklist can have severe consequences, as detailed in our guide on what happens when your domain is on an email blacklist.

Additionally, pay close attention to the new Google and Yahoo sender requirements. These updates emphasize strict authentication (SPF, DKIM, DMARC), low spam rates, and easy unsubscribe options. Adhering to these guidelines from the outset will significantly improve your warming success and long-term deliverability.

Key metrics to track during warmup

Open rate: Aim for consistently high open rates, indicating recipients are interested in your content.
Click-through rate (CTR): High CTRs signal engagement and value to ISPs.
Bounce rate: Keep this below 1% to avoid reputation damage. Address hard bounces immediately.
Spam complaint rate: Maintain this below 0.1%. Even a few complaints can significantly harm your sender reputation.
Unsubscribe rate: While inevitable, keep this low. High unsubscribes indicate poor targeting or content.

Maximizing success with Klaviyo

Successfully warming up a new client's email list in Klaviyo is a marathon, not a sprint. It requires patience, careful planning, and continuous monitoring. By focusing on list hygiene, strategic segmentation, gradual volume increases, engaging content, and diligent metric tracking, you can establish a strong sender reputation and ensure your client's emails consistently reach the inbox. This methodical approach lays the groundwork for long-term email marketing success and high deliverability.

Views from the trenches

Best practices

Start by identifying the most engaged segment of your list, such as recent purchasers or active subscribers.

Use automated flows, like a welcome series, for initial sends to leverage high engagement.

Gradually increase email volume over several weeks, expanding to less engaged segments slowly.

Prioritize sending valuable, non-promotional content during the initial warming period to build trust.

Common pitfalls

Sending to an entire uncleaned list at once, which can lead to high bounce rates and spam complaints.

Ignoring list age; old, dormant lists carry higher risks of deliverability issues and should be handled with extreme care.

Using aggressive promotional content too early, triggering negative recipient feedback.

Not monitoring key metrics like open rates, bounce rates, and spam complaints closely.

Expert tips

Always verify proper list sourcing to ensure all contacts are genuinely opted-in.

Consider asking contacts on older lists to re-opt-in to ensure active consent and engagement.

Make unsubscribe links very easy to find to reduce spam complaints.

Continuously segment your list based on engagement to maintain a healthy sender reputation.

Expert view

An expert from Email Geeks says to ensure the list is properly sourced and to determine its age. If the list is older than a year and has never been emailed, starting fresh might be recommended due to potential negative impacts. If the list is newer and has purchasing history, segmenting by recent purchases is advisable, and the process should be taken slowly, focusing on relationship-building through welcome series content rather than immediate sales.

March 17, 2022 - Email Geeks

Marketer view

A marketer from Email Geeks says that for lists that haven't been mailed in a while, it's essential to clean them with a list cleaning service to remove bouncers, bots, and dormant addresses to improve deliverability.

March 17, 2022 - Email Geeks