CampaignStack vs Instantly: one channel against two

Instantly solved the expensive part of cold email: infrastructure. Every sending plan, including the $47 Growth tier, carries unlimited email accounts and unlimited warmup, so scaling volume means adding inboxes, not upgrading plans. The managed side is real too: order Google accounts through Instantly and they arrive configured with MX, SPF, DKIM and DMARC in 24 to 72 hours, ready to warm. And because pricing meters emails sent and contacts uploaded rather than seats, an agency's whole team works in one account at one price.

The rest of the bundle is broader than most people remember: a 450M-contact database in SuperSearch, a unified inbox across every sending account, a CRM, website visitor identification, and a public API v2 that covers campaigns, leads, accounts and webhooks. For a team whose entire motion is cold email, this is the deepest stack on the market and the price is fair.

Instantly does not run LinkedIn, and does not claim to. A sequence has no LinkedIn step to add, and nothing in the product handles a LinkedIn session or an invite budget, because there is no LinkedIn side at all. That is a coherent choice for a deliverability company, and it is also why the LinkedIn-first tools in this category (HeyReach, Expandi and the rest) all list Instantly as the thing they route email to: in every one of those stacks, Instantly is the email layer and something else does LinkedIn.

CampaignStack runs both channels in one workflow graph. Each LinkedIn account gets its own encrypted browser profile on our server behind a residential proxy, with per-action-type daily budgets, usage-based warm-up, weekly invite caps and an automatic pause on risk signals; email steps run in the same graph with their own send budgets. A lead who accepts an invite on Tuesday does not get the day-one cold email on Wednesday, because one system holds both threads.

Instantly's AI Sales Agent is pitched exactly the way it works: it finds leads, drafts the message, follows up and books the meeting, and the vendor states it can run without human involvement. Setup is quoted at 30 seconds. What the product pages do not describe is any step where a draft gets checked before it reaches a prospect. There is no critique pass, and no queue where a doubtful message waits for a person.

CampaignStack's position is that the draft is the risky part. Every AI draft here faces a critic that reads the full brief and objects with a concrete reason; a draft that keeps failing gets flagged and parked in a review queue where a human approves, edits or rejects it. If you want full autopilot you can run it, but the machinery for not trusting the machine is built in, and for an agency sending in a client's name that machinery is the product.

The honest answer for many teams is not either. Instantly connects to CampaignStack with an API key, and from there the two divide the work: SuperSearch enrichment fills in work emails and profile details, and a generated workflow wires that lookup in front of the email steps without being asked. Leads can push into an Instantly campaign or list, imports come back the other way, and replies, bounces and unsubscribes sync into the lead record here.

So the usual split: Instantly keeps the sending infrastructure it is best at, and CampaignStack runs LinkedIn on your clients' accounts, scores who deserves outreach, drafts against each workspace's playbook and holds the doubtful drafts for review. If cold email volume is the entire programme and LinkedIn is not part of it, stay where you are; this comparison is only close when both channels matter.