New Mail Merge features for onboarding, updates, and marketing emails

Streak’s mail merge lets you send personalized email sequences directly from Gmail — ideal for sales outreach, follow-ups, and customer communication at scale. You can customize each message with variables, automate follow-ups, and track performance without leaving your inbox.

Our latest mail merge update lets you:

✅ Pause or continue your email sequence after replies
🧵 Send email follow-up as new threads with custom subject lines
📭 Ignore OoO replies and vacation responders
🚫 Include unsubscribe links

These new controls make mail merge a powerful tool for marketing-oriented emails like newsletters, onboarding sequences, and promotions. 

Below, we’ll explain how each of these updates give you more control over your email sequences.

Pause or continue the email sequence after a reply

Previously,mail merges and their automatic followups would automatically stop if someone replied to your email. This is typical behavior for sales outreach — but there are many scenarios where you'd want to continue sending an email after receiving a reply.

Now, you can choose whether a reply should pause the sequence or allow it to continue.

For example, a new user might reply “Thanks!” to your first onboarding email — but you still want them to receive the remaining setup tips. Or a subscriber could reply to your newsletter without opting out, and still receive the next edition.

You can now decide what makes sense for your email campaign goals, and adjust your mail merge settings accordingly.

Auto-detect out-of-office and vacation replies

Mail merge now detects when a reply is an out-of-office or vacation responder and can treat these automated replies differently from genuine responses.

Previously, these auto-replies would count as a response and stop the rest of your follow ups from sending. Now, you can keep the sequence going, ensuring your messages reach the recipient once they’re back in their inbox.

This is especially useful for time-sensitive campaigns or scheduled onboarding flows. For example, if someone is out of office during a product launch or welcome sequence, they’ll still receive the rest of your messages when they return — no need to manually restart or recreate the sequence.

Send follow-ups as a reply or start a new thread

You can now choose whether emails in a mail merge sequence send as replies to the previous messages or start a new thread. This setting is available on a per-message basis, giving you full control over how your sequence appears in the recipient's inbox.

Starting a new thread lets you write a fresh subject line for each email — ideal for onboarding, training, or multi-part campaigns where each message covers a distinct topic.

For example, if you're sending a weekly onboarding series, you might want an email sequence with subjects like:

1. "Welcome to [Product]"
2. "3 tips to get more from your dashboard"
3. "Customize your settings in 2 minutes"

In business development or outbound sales, some teams also prefer new threads for follow-ups because it allows more room to test different subject lines or personalize each subject line further.

Whether you're aiming for continuity or looking to introduce a new topic in each subject line, you can now choose what works best for each stage of your sequence.

Include unsubscribe links for marketing emails

Streak now supports unsubscribe links in mail merge emails, making it easier to respect recipients’ preferences and comply with email regulations.

Once someone unsubscribes, they won’t receive mail merge emails from anyone on your team.

You should only remove unsubscribe links for transactional or solicited emails, such as receipts or requested product updates.

Before sending marketing-related emails, be sure to review the email regulations that apply to you — such as CAN-SPAM, GDPR, or other local laws — to stay compliant and maintain trust with your audience.

How to use Streak mail merge for marketing emails

You can now use Mail Merge for onboarding, product updates, and other marketing outreach by adjusting a few key settings — or enabling the "Marketing sequence" option to apply them all at once:

• Start a new thread for each message: write a new subject line and introduce a new topic in each email.
• Ignore out-of-office replies: keep your sequence running even if someone is away.
• Continue sending after replies: make sure replies don’t stop the rest of your sequence.
• Include unsubscribe links: stay compliant and give recipients control.

These settings make Mail Merge more useful for a wider range of communication — all from your Gmail inbox.

Tailor mail merge to support more types of email outreach

These updates unlock a new level of flexibility in Streak mail merge. Mail merge now gives you the control you need to run marketing-style campaigns directly from Gmail. You can decide how your messages send, when follow-ups stop, and how recipients can opt out — all with the flexibility to match your goals.

Whether you're onboarding new users, announcing a product launch, or running a seasonal promotion, mail merge helps you deliver each message with the timing and structure that fits the campaign.

Ready to try it out? Head to your pipeline and start setting up your next mail merge campaign.