Cold Email Infrastructure Playbook for SEA B2B Teams in 2026

Short answer: a cold-email setup is a sequence of decisions, not a tool. Buy separate sending domains, authenticate them, warm the mailboxes, cap volume per inbox, and keep consent and opt-out handling in order. Zapmail automates the mailbox and DNS steps. It does not decide who you may email.

Method: the figures below come from Zapmail's pricing page, help-centre articles and blog, plus Google's bulk-sender rules, all opened on 4 November 2026. No campaigns were sent and no deliverability was measured, so there are no inbox-placement percentages here. Each number is the vendor's own and is traced under Sources.

What does Zapmail actually do in this workflow?

Zapmail describes itself as "cold email infrastructure for Google & Microsoft". Its homepage says it creates US-hosted Google Workspace and Microsoft 365 mailboxes, sets up SPF, DKIM, DMARC and custom tracking domains, and connects the mailboxes to outreach tools. It lists Instantly, Smartlead, ReachInbox, Reply and Lemlist among them. You can buy new domains through it or bring your own, and the homepage says you own purchased domains.

It is not a sending tool, a lead database or a CRM. The sequencing, personalisation and reply handling happen in the outreach tool you connect. See /tools/zapmail for the tool record.

Step 1: Who are you allowed to email?

Do this before buying anything. Cold email law differs by country, and an infrastructure tool will not check it for you.

1. List the countries your recipients sit in, not just where your company is registered.
2. For each, find the official rule on unsolicited commercial email, and on consent where it applies.
3. Decide which segments you will not contact (for example, individuals rather than named business roles).

One example: Singapore has a Spam Control Act; we could not open the statute text (Singapore Statutes Online returned HTTP 403, and the IMDA and PDPC pages we tried did not confirm its scope), so we state no thresholds, labels or deadlines from it. Read the Act yourself, and the Personal Data Protection Act where personal data is involved, before you send. We did not check the laws of Indonesia, Malaysia, the Philippines, Thailand or Vietnam, so take local legal advice for each.

Step 2: How many domains and mailboxes do you need?

Zapmail's blog gives a "3-5-10 rule": at least three inboxes per domain, aim for five, and cap it at ten domains. Its pricing and homepage also say "1 Domain per workspace". Use a separate sending domain, such as a variant of your brand name, so that a reputation problem does not reach your main company domain. Zapmail's warm-up blog makes the same recommendation.

Work backwards from volume. If you plan to send 150 emails a day at 30 per mailbox, you need five mailboxes. With at least three inboxes per domain and five as the target, that is one or two domains.

Step 3: What does it cost?

The pricing page, read 4 November 2026, lists three plans:

Billing can be monthly, quarterly or yearly, with "2 months free" on yearly and up to 20% off quarterly or yearly. The homepage says mailboxes start at "$2.5" each, but the plan table implies USD 3.90 per mailbox on Starter at ten mailboxes, so treat the headline figure as the best case. Two cost notes from the page: Google Workspace mailbox pricing "increases after the first year", and Zapwarm (below) is priced separately. Domains are extra.

Step 4: How are SPF, DKIM and DMARC handled?

Zapmail's homepage says SPF, DKIM, DMARC and custom tracking domains are set up automatically. Zapmail's warm-up article says all three must be configured before campaigns launch. Google's bulk-sender rules, for senders of 5,000 or more messages a day, require SPF and DKIM, require DMARC for the sending domain, and ask senders to keep the spam rate reported in Postmaster Tools below 0.10% and to avoid ever reaching 0.30% or higher.

Cold outreach from a handful of mailboxes will usually be far below 5,000 a day. The same page is still a useful benchmark, and Google also requires one-click unsubscribe for marketing and subscribed messages.

1. After provisioning, confirm each record resolves in a DNS lookup tool.
2. Send a test to a Gmail and a Microsoft address and inspect the headers for SPF, DKIM and DMARC pass.
3. Register the domain in Google Postmaster Tools so you can watch the spam rate.

Step 5: Warm up, or buy pre-warmed?

Zapmail has its own warm-up product, Zapwarm. Its help article says Google mailboxes get a "21-day initial warmup" and Microsoft mailboxes a "35-day initial warmup". Zapwarm costs USD 2.00 per mailbox per month for 1 to 30 mailboxes, USD 1.50 for 31 to 100 and USD 1.00 for 101 or more, and the first month is free.

The alternative is pre-warmed mailboxes. The vendor's help article lists these limits:

• They run for 12 months only and cannot be renewed or extended.
• They are not refundable once provisioned.
• They are available only on Zapmail's pre-warmed domains, not on your own.
• Changing the username resets the warm-up history.
• Deliverability improvements are "indicative, not guaranteed".

If your brand domain matters, buy new domains and warm them. If you want a 12-month campaign and no brand attachment, pre-warmed is a fit.

Step 6: How many emails per inbox per day?

Zapmail's own materials disagree on details, so pick the more conservative number and watch your results.

• The scaling guide says to aim for 30 to 50 cold emails per mailbox per day, and notes that some setups reach 200 to 300 after four to six weeks of warming while most users should keep a 50-email cap.
• The same guide's ramp is 3 to 10 emails in week 1, 10 to 25 in week 2, 25 to 50 in week 3 and 50 to 100 or more in week 4.
• The warm-up article is slower: 5 to 10 a day at the start, 10 to 20 once campaigns begin, then increases of 20 to 50% a week. It puts warm-up at two to four weeks for established domains and up to three months for brand-new ones.
• Zapwarm's help article says each mailbox gets a recommended daily volume from its sending history, warm-up progress and deliverability signals.

The slower schedule is the safer starting point. Zapmail's scaling guide also suggests removing contacts after six months or more without engagement.

Step 7: How do you connect and monitor?

1. Connect each mailbox to your outreach tool through the export or integration flow in Zapmail's help centre.
2. Add an unsubscribe line and an honest sender identity to every sequence.
3. Run an inbox-placement test. The pricing page includes 3, 10 or 30 free deliverability test credits a month on Starter, Growth and Pro.
4. Pause any mailbox whose replies turn to complaints, and review the list source before resuming.

Who should not use Zapmail?

• A team that needs one or two normal company inboxes. Buy Google Workspace or Microsoft 365 directly. Google's Thailand pricing page, read 4 November 2026, lists Business Starter at THB 275 per user per month on the annual plan, excluding tax (THB 137.50 for 12 months on a 50% promotion limited to 20 users).
• A team without permission to email its list. Infrastructure does not fix consent.
• Anyone unwilling to depend on a third party for mailbox and domain operations. Check workspace ownership, renewal pricing and the recovery process first, as our tool record also advises.
• Teams that want a guarantee of inbox placement. The vendor itself calls improvements indicative, not guaranteed.
• Brands whose main domain cannot risk a reputation problem. Keep it separate from outreach domains regardless of tool.

What are the honest alternatives?

Buying Google Workspace directly gives you mailboxes and admin control, with DNS and warm-up done by hand. That is cheaper to understand and slower to scale. Our guide to free custom-domain email with Cloudflare and Brevo covers the ordinary company-inbox case, which is a different job from outbound.

For the CRM side of outbound, see CRM tools for SEA sales teams.