Instantly vs Mailforge
An independent, review-free comparison compiled by the SaaSTracker editorial team. Both products are profiled in full, and neither can pay for placement here.
The short answer
Editorial assessmentMailforge compared with Instantly
Not competitors: Instantly is the sending platform and Mailforge is what you plug into it. Instantly does sell its own done-for-you accounts marketplace, so there is overlap at the point of purchase, and buying both from Instantly is simpler. Buying Mailforge separately is usually cheaper per mailbox and keeps your infrastructure portable if you ever change sequencer, which is the stronger long-term argument.
Choose Instantly if
Agencies and outbound teams sending high-volume cold email across many mailboxes, who want warm-up, rotation, and reply management in one place.
Choose Mailforge if
Small businesses and agencies that have chosen a sending platform and now need ten to a few hundred secondary mailboxes on properly configured domains, without spending a weekend in a registrar's DNS panel or risking their primary company domain.
Side by side
13 attributes| Attribute | Instantly | Mailforge |
|---|---|---|
| Category | Cold Email | Cold Email |
| Starting price | $37/mo (14 days trial) | $3 per mailbox slot per month billed yearly, ten-slot minimum, so about $30 per month (free trial) |
| Pricing model | Flat monthly tiers metered by uploaded contacts and monthly email volume; sending accounts and warm-up are never metered. The lead database and website-visitor products are separate subscriptions. | Slot-based subscription for mailbox capacity, billed monthly or annually with a ten-slot minimum, plus separate per-year domain registration and an optional per-domain SSL add-on. |
| Free plan | No | No |
| Free trial | 14 days | None; this is provisioned infrastructure with real domain and hosting costs behind it |
| Best for | Agencies and outbound teams sending high-volume cold email across many mailboxes, who want warm-up, rotation, and reply management in one place. | Small businesses and agencies that have chosen a sending platform and now need ten to a few hundred secondary mailboxes on properly configured domains, without spending a weekend in a registrar's DNS panel or risking their primary company domain. |
| Setup time | Under an hour to first campaign; 2-4 weeks of warm-up before meaningful volume should send. | Minutes to buy and provision, but plan for two to three weeks before meaningful volume. Domains register and DNS propagates quickly, mailbox creation is bulk and fast, and then warm-up and ramp-up set the real timeline. |
| Learning curve | Low for basic campaigns; moderate to run the full playbook (domain strategy, ramp schedules, rotation tuning). The community's shared playbooks flatten it considerably. | Low for the tool, moderate for the discipline. The interface is a calculator and a provisioning screen. What is hard is knowing how many mailboxes per domain to run, what daily caps to hold, and when to retire a mailbox, and Mailforge helps with the first of those and not the others. |
| Platforms | Web app, Chrome extension (lead reveal), REST API | Web app, Bulk domain and mailbox provisioning console |
| Compliance | GDPR-aligned processes, CAN-SPAM tooling (unsubscribe links, sending caps) | SPF, DKIM, and DMARC configured automatically on every provisioned domain, Sender obligations under CAN-SPAM and GDPR remain entirely with you as the sender, since Mailforge supplies infrastructure and never touches your campaign content |
| Founded | 2021 | 2022 |
| Headquarters | Tallinn, Estonia (remote-first) | Tallinn, Estonia |
| Ownership | Bootstrapped | Founder-led, largely bootstrapped with a small early round |
Strengths and limitations
Instantly
Strengths
- Unlimited accounts + free warm-up on every tier makes scaled sending economics unbeatable at the entry level.
- Unibox is the best reply-triage surface in the category for operators running many mailboxes.
- Fast, operator-driven release cadence; features arrive weeks after the community asks.
- Self-serve throughout, from trial to 100 mailboxes without talking to sales.
Limitations
- Email-only sequences; no native calls, LinkedIn, or SMS steps.
- Lead database accuracy trails dedicated providers (Apollo, Clay waterfalls) on harder segments.
- The CRM layer is thin, teams with real pipeline process still need HubSpot/Pipedrive downstream.
- Warm-up networks operate against mailbox-provider terms; providers periodically tighten detection, an inherent category risk.
Mailforge
Strengths
- Removes the single most tedious and error-prone part of running cold email, which is provisioning domains and writing SPF, DKIM, and DMARC records correctly at scale.
- Slot-based pricing means deleting and recreating burned mailboxes costs nothing, which matches how outbound programs actually behave.
- At about $3 a mailbox per month on annual billing, it is at the cheap end of the infrastructure market.
- The sizing calculator is genuinely useful and steers new buyers away from stacking too many mailboxes on one domain.
Limitations
- It is not a sending platform, so it is always a second purchase alongside a sequencer, which some buyers do not realize until after checkout.
- Shared infrastructure means you do not control the sending behavior of other customers on the same platform, which is precisely why the vendor also sells Primeforge and Infraforge.
- No warm-up included, so a fresh Mailforge setup is not ready to send at volume on day one and needs another subscription.
- Ten-slot minimum excludes small users who just want two or three extra mailboxes.
Pricing compared
Instantly
Flat monthly tiers metered by uploaded contacts and monthly email volume; sending accounts and warm-up are never metered. The lead database and website-visitor products are separate subscriptions.
- Growth$37
- Hypergrowth$97
- Light Speed$358
- EnterpriseCustom
At entry price, Instantly's unmetered accounts and warm-up undercut any per-seat sequencer for volume senders; the real total cost is mailboxes and domains, which scale linearly no matter the platform. The database add-on is priced to tempt but is weaker than dedicated data tools.
Mailforge
Slot-based subscription for mailbox capacity, billed monthly or annually with a ten-slot minimum, plus separate per-year domain registration and an optional per-domain SSL add-on.
- Mailbox slots, annual billing$3
- Mailbox slots, monthly billing$5
- Domain registration$14
- SSL and domain masking add-on$2
At $3 a slot annually, Mailforge is among the cheapest ways to get authenticated mailboxes at scale. Model it properly: sending 10,000 emails a month at a conservative 30 a day per mailbox needs roughly eleven to fifteen mailboxes, so about $45 a month of slots plus two or three domains, which is genuinely cheap next to the sequencer bill. At 100,000 a month you need on the order of 110 to 150 mailboxes, about $330 to $450 a month of slots plus twenty to thirty domains, and at that point the shared-infrastructure question becomes the real decision rather than the price. Compare that against Primeforge at $4.50 a slot for genuine Workspace and Microsoft 365 mailboxes and the premium for real provider mailboxes is only about 50 percent, which is a smaller gap than most buyers assume.
Editorial verdict on each
Instantly
Category LeaderInstantly is the default answer for scaled cold email in 2026, and deservedly so: the unlimited-account architecture, bundled warm-up, and Unibox make it the cheapest and smoothest way to run serious volume. Its edges, thin CRM, email-only sequences, merely adequate data, are the deliberate cost of that focus. Volume-driven agencies and founder-led outbound should start here; teams needing multichannel process or enterprise governance should look at the sales-engagement category instead.
Read the full Instantly profileMailforge
InnovationMailforge does one unglamorous job well: it turns the multi-hour ritual of registering domains and hand-writing SPF, DKIM, and DMARC records into a calculator and a checkout, at about $3 a mailbox per month. If you have already picked a sending platform and need ten to a few hundred secondary mailboxes without touching your company domain, it is among the cheapest and least annoying ways to get them, and slot-based billing correctly rewards retiring burned mailboxes. Two things should govern the decision. First, this is infrastructure, not a sequencer, and it is always a second bill. Second, it is the shared tier of a ladder whose upper rungs exist for a reason: if inbox placement is your binding constraint rather than cost per mailbox, the extra $1.50 a slot for real Workspace mailboxes from Primeforge is usually the better buy.
Read the full Mailforge profileInstantly profile last reviewed 2026-08-22; Mailforge last reviewed 2026-08-22. Pricing is compiled from public sources and can change without notice. See our methodology.