sending.ac review: $199 for 350 Azure inboxes that send 4 emails a day each

sending.ac sells Azure inboxes, Exchange Online mailboxes in one Microsoft tenant per domain, at $199 a month for 350 or $499 for 1,000, with domains bought separately and sending in your own sequencer. Its own calculator gives each inbox 4 outreach emails a day, so 2,500 cold emails a day take 625 inboxes: $447.25 a month with Instantly, before domains. 100 Outreach2day mailboxes send the same for $171.67 with warmup and our sequencer.

Price 100 mailboxes1,000+ mailboxes? Book a call
  • Warmup and sending included
  • $2.50 a mailbox, 12 minimum
  • Month-to-month billing

Monthly cost · 25,000 cold emails a day, sending included

  1. sending.ac + Instantlysending.ac + Instantly: from $3,830
  2. Outreach2day mailboxes + InstantlyOutreach2day mailboxes + Instantly: $1,422.67
  3. Outreach2day all-inOutreach2day all-in: $716.67
Price per mailbox
from $0.50 (Agency, 1,000 inboxes for $499); $0.57 on Growth
Outreach2day per mailbox
$2.50 month to month, $1.50 from 100, $0.50 from 1,000
Smallest order
Growth, $199 a month for 350 inboxes, plus domains
Mailbox types
Microsoft
Warmup
Pre-warmed on the Prewarmed option; otherwise warmup runs in your sequencer
MCP server
MCP server at mcp.builders.ac on every plan

Every line item from 2,500 to 1,000,000 cold emails a day

Fit

Who sending.ac fits

Pick sending.ac if

  • You want Azure inboxes for Outlook-heavy lists at about $0.50 each
  • You want each domain on its own Microsoft tenant
  • You already pay for Smartlead, Instantly, PlusVibe or EmailBison

Look elsewhere if

  • You want more than 4 cold emails an inbox a day
  • You want warmup and sending in the mailbox price
  • You want a refund window or published domain prices
  • You want Google Workspace mailboxes today

Overview

What sending.ac is

sending.ac is run by Scale with Value Limited, a company incorporated in Hong Kong, and its terms fall under Hong Kong law. Its CEO says it started in 2024. It provisions domains, DNS and Azure inboxes and connects them to Smartlead, Instantly, PlusVibe or EmailBison; it is not a sequencer, and Google Workspace mailboxes are on a waitlist.

The design is one Microsoft tenant per domain with "your own IPs, your own reputation, your own admin panel per domain", and up to 75 inboxes on one domain. Domains come from its pool of aged domains or from you. Both plans include its APIs (in alpha and beta) and an MCP server, mailbox insurance on the plans that include it, and 7 deliverability checks per domain a day.

Since July 2026 sending.ac has been promoted in LinkedIn posts by several cold email creators. One of them, on 2026-10-15, wrote that sending.ac had asked him to partner on posts; the others carry no label. The claims in those posts are checked against the vendor's own pages below.

Azure inboxes for cold email, one Microsoft tenant per domain and up to 75 inboxes a domain, connected to the sequencer you run; no sequencer source (opens the vendor's page in a new tab)

Operated by Scale with Value Limited, a company incorporated in Hong Kong; started in 2024 source (opens the vendor's page in a new tab)

Pricing

sending.ac pricing

What sending.ac charges and what the price includes, next to Outreach2day. Each cell links the page it comes from.

List prices from sending.ac's pricing page and Outreach2day's pricing page, checked . Taxes and card fees excluded.

Add-ons and extra costs

Two plans on monthly billing: Growth at $199 for 350 Azure inboxes ($0.57 each) with extras at $0.55, and Agency at $499 for 1,000 ($0.50) with extras at $0.50; from 1,100 inboxes the plan builder prices any count at $0.50. Quarterly billing is $179 and $449 a month, yearly $165 and $415.

Two things sit outside the plan. Domains are bought separately and the site shows no price for them. The Prewarmed toggle, inboxes that send the day they arrive, adds a one-time $399 on Growth or $999 on Agency.

The plan cards say about 1,500 outreach emails a day on Growth and 4,000 on Agency: 4 an inbox a day, the figure its calculator uses. Our cost table uses it, 75 inboxes a domain and Instantly for sending and warmup.

Full cost

What 2,500, 5,000 and 25,000 cold emails a day cost with sending.ac

The same emails a day on every row: sending.ac mailboxes at its own limit of 4 a day with the Instantly plan it needs to send and warm up, next to Outreach2day mailboxes (25 a day each) in Instantly and Outreach2day on its own.

2,500 a day · 55,000 a month625 sending.ac mailboxes at 4 a day, 100 of ours at 25 · USD a month
  1. sending.ac + Instantlysending.ac + Instantly: from $447.25
  2. Outreach2day mailboxes + InstantlyOutreach2day mailboxes + Instantly: $268.67
  3. Outreach2day all-inOutreach2day all-in: $171.67
5,000 a day · 110,000 a month1,250 sending.ac mailboxes at 4 a day, 200 of ours at 25 · USD a month
  1. sending.ac + Instantlysending.ac + Instantly: from $808
  2. Outreach2day mailboxes + InstantlyOutreach2day mailboxes + Instantly: $527.33
  3. Outreach2day all-inOutreach2day all-in: $343.33
25,000 a day · 550,000 a month6,250 sending.ac mailboxes at 4 a day, 1,000 of ours at 25 · USD a month
  1. sending.ac + Instantlysending.ac + Instantly: from $3,830
  2. Outreach2day mailboxes + InstantlyOutreach2day mailboxes + Instantly: $1,422.67
  3. Outreach2day all-inOutreach2day all-in: $716.67
  • sending.ac + Instantly

    Azure mailboxes from $0.50 (Agency, 1,000 inboxes for $499); $0.57 on Growth · 4 cold emails a day each; Instantly for sending and warmup

    2,500 a day · 55,000 a month

    from $447.25a month

    at least $275.58 more than Outreach2day all-in

    from $8.13 per 1,000 emails · 625 mailboxesMailboxes alone: $350.25 a month

    5,000 a day · 110,000 a month

    from $808a month

    at least $464.67 more than Outreach2day all-in

    from $7.35 per 1,000 emails · 1,250 mailboxesMailboxes alone: $624 a month

    25,000 a day · 550,000 a month

    from $3,830a month

    at least $3,113.33 more than Outreach2day all-in

    from $6.96 per 1,000 emails · 6,250 mailboxesMailboxes alone: $3,124 a month

  • Outreach2day mailboxes + Instantly

    Keep Instantly, buy the mailboxes from us; 25 a day each

    2,500 a day · 55,000 a month

    $268.67a month

    $97 more than Outreach2day all-in

    $4.88 per 1,000 emails · 100 mailboxesMailboxes alone: $150 a month

    5,000 a day · 110,000 a month

    $527.33a month

    $184 more than Outreach2day all-in

    $4.79 per 1,000 emails · 200 mailboxesMailboxes alone: $300 a month

    25,000 a day · 550,000 a month

    $1,422.67a month

    $706 more than Outreach2day all-in

    $2.59 per 1,000 emails · 1,000 mailboxesMailboxes alone: $500 a month

  • Outreach2day all-in

    Mailboxes, warmup and our sequencer in one bill; 25 a day each

    2,500 a day · 55,000 a month

    $171.67a month

    $3.12 per 1,000 emails · 100 mailboxesMailboxes alone: $150 a month

    • 100 mailboxes at $1.50 (volume price from 100), warmup and sequencer included: $150
    • 20 domains at $13 a year: $21.67
    5,000 a day · 110,000 a month

    $343.33a month

    $3.12 per 1,000 emails · 200 mailboxesMailboxes alone: $300 a month

    • 200 mailboxes at $1.50 (volume price from 100), warmup and sequencer included: $300
    • 40 domains at $13 a year: $43.33
    25,000 a day · 550,000 a month

    $716.67a month

    $1.30 per 1,000 emails · 1,000 mailboxesMailboxes alone: $500 a month

    • 1,000 mailboxes at $0.50 (volume price from 1,000), warmup and sequencer included: $500
    • 200 domains at $13 a year: $216.67

Compared at the same emails a day, each vendor at its own published emails per mailbox a day: a cheap mailbox that sends 5 a day costs more per email than one that sends 25. Mailboxes = emails a day ÷ emails per mailbox a day (sending.ac: 4, its own recommendation; Outreach2day: 25). A month is 22 sending days, so emails a month = emails a day × 22. Monthly list prices on monthly billing; the Instantly plan is the cheapest one that covers the volume. sending.ac does not publish a domain price, so its domains (75 mailboxes each) are left out of the total, marked "from"; Outreach2day .com domains at $13 a year, 5 mailboxes per domain. Domains spread over 12 months. Outreach2day mailboxes on comparison pages: $2.50 a mailbox up to 99, $1.50 from 100, $0.50 from 1,000; larger volumes on the Enterprise plan. A mailbox-only vendor cannot send campaigns on its own, so its total is the full sending setup: its mailboxes, domains and the sequencer plan that covers the volume. Instantly is the reference sequencer, on its published plans for the emails and new contacts a month (emails ÷ 3); Smartlead where Instantly publishes no plan; Mailforge with Salesforge, because its mailboxes cannot be warmed in Instantly. The mailbox line is listed on its own in every cell.

Your saving · 25,000 a day

You save $3,113.33 a month ($37,360 a year)with Outreach2day at 25,000 cold emails a day, against sending.ac + Instantly at list prices

We move your mailboxes and campaigns for you, free

New · Outreach2day volume pricing

The mailbox price falls from 100 and again from 1,000 mailboxes

Warmup, the sequencer and the replies inbox included at every tier

  1. Up to 99 mailboxes$2.50a mailbox a month
  2. From 100 mailboxes$1.50a mailbox a month
  3. From 1,000 mailboxes$0.50a mailbox a month

Enterprise plan. Better prices for larger volumes.

Book a call

Emails per mailbox

Each Outreach2day mailbox sends 25 cold emails a day from day 14, sending.ac's 4: 6.25× the volume per mailbox

Outreach2day, full setup per 1,000 emails
$3.12
All in: $171.67 a month, sequencer and warmup included. Mailboxes alone: $1.50 ÷ (25 × 22) = $2.73
sending.ac, full setup per 1,000 emails
from $8.13
With Instantly Hypergrowth: from $447.25 a month. Mailboxes alone: $0.56 ÷ (4 × 22) = $6.37

2,500 cold emails a day (625 sending.ac mailboxes, 100 of ours), 22 sending days. sending.ac sells mailboxes only, so its full setup adds the sequencer that sends them; every line is in the cost table.

Cold emails a mailbox a day
  1. Outreach2dayOutreach2day: 25 a day
  2. sending.acsending.ac: 4 a day

At 2,500 cold emails a day sending.ac needs 625 inboxes at 4 a day: Growth with 275 extras ($350.25), 9 domains at a price the site does not show, and Instantly Hypergrowth for sending and warmup ($97), from $447.25 a month. 100 Outreach2day mailboxes cost $171.67 with domains, or $268.67 in the same Instantly plan.

At 5,000 a day sending.ac is from $808 against $343.33; at 25,000 a day, from $3,830 against $716.67, with our mailboxes at $0.50 from 1,000. Switching on Prewarmed adds $399 or $999 once.

What sending.ac does well

  • A low price per inbox: $0.50 on Agency
  • One tenant per domain, so one tenant's block stays on one domain
  • API and MCP server on both plans
  • Mailbox insurance with a 30-day replacement on the plans that include it

Verdict

sending.ac sells cheap Azure inboxes with a tenant per domain, an API and an MCP server. Each inbox sends 4 outreach emails a day on its own numbers, domains are an extra bill, the sequencer is another, and payments are not refundable, so the same volume takes six times the inboxes and two more subscriptions.

Outreach2day is $2.50 a mailbox month to month, $1.50 from 100 and $0.50 from 1,000, with warmup for the life of the mailbox, 25 cold emails a day from day 14 and our own sequencer. Keep Instantly or Smartlead if you like: our mailboxes sync in by API key.

At scale

From 25,000 to 1,000,000 cold emails a day

The same setups at larger daily volumes. A vendor without a published price at a size reads “Custom pricing (not published)” and has no bar.

Running 25,000+ a day? Enterprise plan: better prices for larger volumes.Book a call

25,000 a day · 550,000 a month1,000 mailboxes · USD a month
  1. sending.ac + Instantlysending.ac + Instantly: from $3,830
  2. Outreach2day mailboxes + InstantlyOutreach2day mailboxes + Instantly: $1,422.67
  3. Outreach2day all-inOutreach2day all-in: $716.67
50,000 a day · 1,100,000 a month2,000 mailboxes · USD a month
  1. sending.ac + Instantlysending.ac + Instantly: from $7,564
  2. Outreach2day mailboxes + InstantlyOutreach2day mailboxes + Instantly: $2,748.33
  3. Outreach2day all-inOutreach2day all-in: $1,433.33
100,000 a day · 2,200,000 a month4,000 mailboxes · USD a month
  1. sending.ac + Instantlysending.ac + Instantly: from $15,119
  2. Outreach2day mailboxes + InstantlyOutreach2day mailboxes + Instantly: $5,486.67
  3. Outreach2day all-inOutreach2day all-in: $2,866.67
250,000 a day · 5,500,000 a month10,000 mailboxes · USD a month
  1. Outreach2day all-inOutreach2day all-in: $7,166.67
sending.ac + Instantly, Outreach2day mailboxes + Instantly: no published price at this volume, so no bar.
500,000 a day · 11,000,000 a month20,000 mailboxes · USD a month
  1. Outreach2day all-inOutreach2day all-in: $14,333.33
sending.ac + Instantly, Outreach2day mailboxes + Instantly: no published price at this volume, so no bar.
1,000,000 a day · 22,000,000 a month40,000 mailboxes · USD a month
  1. Outreach2day all-inOutreach2day all-in: $28,666.67
sending.ac + Instantly, Outreach2day mailboxes + Instantly: no published price at this volume, so no bar.
Monthly cost of sending.ac and Outreach2day setups from 25,000 to 1,000,000 cold emails a day
Setup25,000 a day550,000 a month1,000 mailboxes50,000 a day1,100,000 a month2,000 mailboxes100,000 a day2,200,000 a month4,000 mailboxes250,000 a day5,500,000 a month10,000 mailboxes500,000 a day11,000,000 a month20,000 mailboxes1,000,000 a day22,000,000 a month40,000 mailboxes
sending.ac + Instantlyfrom $3,830$3,113.33 morefrom $7,564$6,130.67 morefrom $15,119$12,252.33 moreCustom pricing (not published)Custom pricing (not published)Custom pricing (not published)
Outreach2day mailboxes + Instantly$1,422.67$706 more$2,748.33$1,315 more$5,486.67$2,620 moreCustom pricing (not published)Custom pricing (not published)Custom pricing (not published)
Outreach2day all-in$716.67$1,433.33$2,866.67$7,166.67$14,333.33$28,666.67

Mailboxes = emails a day ÷ emails per mailbox a day (sending.ac: 4; Outreach2day: 25). A month is 22 sending days, so emails a month = emails a day × 22. The Instantly plan is the published plan that covers the volume (its contacts and emails); where a vendor publishes no price at that size, the cell says so and the chart leaves it out. Domains at each vendor's published price spread over 12 months; Outreach2day .com domains at $13 a year, 5 mailboxes per domain, are in every total.

Every line at scale

  • sending.ac + Instantly, 25,000 a day: Agency + 5,250 extra inboxes at $0.50 ($3,124) source (opens the vendor's page in a new tab) + 84 domains, price not published (not published) + Instantly Hypergrowth + 7 Outbound add-ons (sequencer, warmup) ($706) = from $3,830
  • sending.ac + Instantly, 50,000 a day: Agency + 11,500 extra inboxes at $0.50 ($6,249) source (opens the vendor's page in a new tab) + 167 domains, price not published (not published) + Instantly Hypergrowth + 14 Outbound add-ons (sequencer, warmup) ($1,315) = from $7,564
  • sending.ac + Instantly, 100,000 a day: Agency + 24,000 extra inboxes at $0.50 ($12,499) source (opens the vendor's page in a new tab) + 334 domains, price not published (not published) + Instantly Hypergrowth + 29 Outbound add-ons (sequencer, warmup) ($2,620) = from $15,119
  • Outreach2day mailboxes + Instantly, 25,000 a day: 1,000 Outreach2day mailboxes at $0.50 (volume price from 1,000) ($500) + 200 domains at $13 a year ($216.67) + Instantly Hypergrowth + 7 Outbound add-ons (sequencer, warmup) ($706) = $1,422.67
  • Outreach2day mailboxes + Instantly, 50,000 a day: 2,000 Outreach2day mailboxes at $0.50 (volume price from 1,000) ($1,000) + 400 domains at $13 a year ($433.33) + Instantly Hypergrowth + 14 Outbound add-ons (sequencer, warmup) ($1,315) = $2,748.33
  • Outreach2day mailboxes + Instantly, 100,000 a day: 4,000 Outreach2day mailboxes at $0.50 (volume price from 1,000) ($2,000) + 800 domains at $13 a year ($866.67) + Instantly Hypergrowth + 29 Outbound add-ons (sequencer, warmup) ($2,620) = $5,486.67
  • Outreach2day all-in, 25,000 a day: 1,000 mailboxes at $0.50 (volume price from 1,000), warmup and sequencer included ($500) + 200 domains at $13 a year ($216.67) = $716.67
  • Outreach2day all-in, 50,000 a day: 2,000 mailboxes at $0.50 (volume price from 1,000), warmup and sequencer included ($1,000) + 400 domains at $13 a year ($433.33) = $1,433.33
  • Outreach2day all-in, 100,000 a day: 4,000 mailboxes at $0.50 (volume price from 1,000), warmup and sequencer included ($2,000) + 800 domains at $13 a year ($866.67) = $2,866.67
  • Outreach2day all-in, 250,000 a day: 10,000 mailboxes at $0.50 (volume price from 1,000), warmup and sequencer included ($5,000) + 2,000 domains at $13 a year ($2,166.67) = $7,166.67
  • Outreach2day all-in, 500,000 a day: 20,000 mailboxes at $0.50 (volume price from 1,000), warmup and sequencer included ($10,000) + 4,000 domains at $13 a year ($4,333.33) = $14,333.33
  • Outreach2day all-in, 1,000,000 a day: 40,000 mailboxes at $0.50 (volume price from 1,000), warmup and sequencer included ($20,000) + 8,000 domains at $13 a year ($8,666.67) = $28,666.67

Why each plan at scale

Your size

What 2,500 cold emails a day cost a month

121,000+
  • sending.ac + Instantlysending.ac + Instantlyfrom $447.25

    625 mailboxes × 4 a day = 2,500 cold emails a day

  • Outreach2day mailboxes + InstantlyOutreach2day mailboxes + Instantly$268.67

    100 mailboxes × 25 a day = 2,500 cold emails a day

  • Outreach2day all-inOutreach2day all-in$171.67

    100 mailboxes × 25 a day = 2,500 cold emails a day

You save $275.58 a month ($3,307 a year)with Outreach2day at 2,500 cold emails a day, against sending.ac + Instantly at list prices

We move your mailboxes and campaigns for you, free

Buy 100 mailboxes

Switching

Moving from sending.ac to Outreach2day

  1. Keep your sequencer

    Connect Instantly or Smartlead in Outreach2day with an API key and the warm mailboxes are added to your account; other tools take a CSV in their import format, or SMTP/IMAP logins. How the export works

  2. Or move the campaigns

    Our sequencer runs campaigns with steps, a send schedule, stop on reply and one inbox for replies; import the contacts as a CSV and recreate the steps. The mailbox price stays $2.50.

  3. Warmup and the overlap

    New mailboxes warm for 14 days before cold email, and warmup keeps running after that. Keep the sending.ac mailboxes sending during those two weeks, then shift the volume and cancel sending.ac for the end of its billing period.

sending.ac's terms make subscription, domain and setup fees non-refundable, partial months included, so time the move to the end of a billing cycle. Order Outreach2day mailboxes 14 days before, let the Azure inboxes finish their follow-ups, then cancel through the chat bubble on its site. Domains you connected stay yours; a domain supplied as part of its managed infrastructure may stay under sending.ac's control unless your plan says otherwise.

Terms

sending.ac limits, setup and terms

Each line links to the vendor's page it comes from.

Smallest order

source (opens the vendor's page in a new tab)
Growth, $199 a month for 350 inboxes, plus domains

Setup time

source (opens the vendor's page in a new tab)
The first domain set can be live the day you sign up; warmup still takes its usual few weeks

Mailbox types

source (opens the vendor's page in a new tab)
Azure inboxes (Exchange Online in a Microsoft tenant), one tenant per domain; Google Workspace on a waitlist

Domains

source (opens the vendor's page in a new tab)
Bought separately from its pool of aged domains, or your own; up to 75 inboxes a domain

Sending limits

source (opens the vendor's page in a new tab)
Up to 4 outreach emails an inbox a day on its own calculator; up to 75 inboxes a domain

Warmup

source (opens the vendor's page in a new tab)
Partly, or at extra cost Pre-warmed on the Prewarmed option; otherwise warmup runs in your sequencer

Sequencers

source (opens the vendor's page in a new tab)
Smartlead, Instantly, PlusVibe and EmailBison

API

source (opens the vendor's page in a new tab)
Included Mailbox, deliverability and provisioning APIs on every plan, in alpha and beta

MCP server

source (opens the vendor's page in a new tab)
Included MCP server at mcp.builders.ac on every plan

Support

source (opens the vendor's page in a new tab)
Calls with the founder or a deliverability advisor, a chat bubble on the site; no SLA published

Refunds

source (opens the vendor's page in a new tab)
"No Refunds" as the general rule; exceptions for billing errors and a prolonged outage, at its discretion

Trial

source (opens the vendor's page in a new tab)
No free trial terms published; free warmup checks for mailboxes bought elsewhere

Features

Other sending.ac features

Mailbox insurance
Replacement within 30 days if a mailbox burns, "on the plans that include it" source (opens the vendor's page in a new tab)
Monitoring
7 deliverability checks per domain a day, 28 days of history source (opens the vendor's page in a new tab)

In detail

The LinkedIn claims, checked against sending.ac's site

"350 for $199" (a LinkedIn post on 2026-10-30): matches the Growth plan. Domains and the optional Prewarmed fee are extra.

"$0.5 a mailbox, no setup fee" (a LinkedIn post on 2026-07-14): partly. $0.50 is the Agency rate and the rate from 1,100 inboxes; Growth works out to $0.57, and extras on it are $0.55. There is no setup fee on the base plans, while the Prewarmed option costs $399 or $999 once.

"$176 a month for 400" (a LinkedIn post on 2026-09-16, with 400 mailboxes sending 3 each): the site lists no such price. 400 inboxes on Growth are $199 + 50 × $0.55 = $226.50 a month on monthly billing. The same post set $176 against $2,400 a month for another setup; neither figure is on sending.ac's pages.

"50 domains = 50 Azure tenants" (a LinkedIn post on 2026-07-28): the site says "one tenant per domain" and "your own IPs" per domain. That the tenants and IPs are separate can't be checked from outside, so read it as the vendor's description of its setup.

A tenant per domain and MC1454397

Microsoft sets the external recipient quota per tenant: 500 × licenses^0.7 + 9,500 a day, and under MC1454397 a new tenant gets 10% of it for its first 30 days and 25% until day 60, while a trial tenant gets 500 a day. Microsoft's posts set no cap on inboxes per tenant and say nothing about Azure inbox prices.

At sending.ac's 4 emails an inbox a day, 75 inboxes on one domain send about 300 external emails a day plus warmup, under the new-tenant quota of a one-license tenant (1,000 a day). The low per-inbox rate, more than the tenant count, is what keeps each tenant inside its quota. What a tenant per domain does change is the blast radius: a tenant that sends too much spam or bulk mail gets 550 5.7.705, and outbound mail stops for every inbox in it. The full Microsoft side is in MC1454397 and the new-tenant limits and Azure inboxes for cold email.

Sending, warmup and where the volume comes from

sending.ac connects its inboxes to your sequencer, so warmup and sending run on that plan. Its FAQ says warmup "still takes its usual few weeks", and the Prewarmed toggle sells inboxes that skip it. With 4 emails an inbox a day, the inbox count grows with the volume: 2,500 a day is 625 inboxes, 25,000 a day is 6,250.

Outreach2day mailboxes are SMTP/IMAP on our own infrastructure, outside Microsoft's tenant quotas, and send up to 25 cold emails a day from day 14 with warmup included for the life of the mailbox. Our mailboxes land in the inbox. Most people think only Google gets to the inbox and overpay for it. Moving off Microsoft tenants step by step is on switching from Microsoft 365.

Ratings

sending.ac ratings

Trustpilot showed no reviews for sending.ac on 2026-11-04, and G2 refused our check, so we show no score.

Or us

sending.ac or Outreach2day

We sell cold email mailboxes too. Where our product fits this buyer and where it does not.

sending.ac

Stay with sending.ac if

  • You need fewer than 12 mailboxes: our minimum order is 12
  • You want a separate Microsoft tenant for every domain

Outreach2day

Outreach2day fits if

  • You run 100+ mailboxes: $1.50 a mailbox from 100 and $0.50 from 1,000, warmup and the sequencer included; larger volumes on the Enterprise plan
  • You want 25 cold emails a mailbox a day from day 14
  • You want warmup and a sequencer in the mailbox price
  • You want mailboxes outside Microsoft's tenant quotas
  • You want $1.50 from 100 and $0.50 from 1,000, month to month
Price 100 mailboxes1,000+ mailboxes? Book a call

Outreach2day mailboxes send from its own campaigns or from your sequencer; the fields and settings per tool are in the integration docs.

FAQ

sending.ac review: questions

How much does sending.ac cost?

$199 a month for 350 Azure inboxes on Growth, $0.55 for each extra, or $499 for 1,000 on Agency, $0.50 each extra; from 1,100 inboxes $0.50 each. Quarterly and yearly billing cost less. Domains are bought separately, and the Prewarmed option is $399 or $999 once.

Is sending.ac legit?

Its terms name Scale with Value Limited, a company incorporated in Hong Kong. Trustpilot showed no reviews for sending.ac on 2026-11-04, and one of the creators promoting it disclosed a partnership with it on LinkedIn.

Does sending.ac give each domain its own Azure tenant?

Its site says "one tenant per domain" with its own IPs, admin panel and reputation. Microsoft's quotas apply per tenant, so a block such as 550 5.7.705 stops the inboxes of one domain.

How many emails can a sending.ac inbox send?

Its own calculator says up to 4 outreach emails an Azure inbox a day: about 1,500 a day on Growth and 4,000 on Agency. An Outreach2day mailbox sends up to 25 cold emails a day from day 14.

Is "$176 for 400 mailboxes" a real sending.ac price?

Not on its pages on 2026-11-04. 400 inboxes on Growth are $226.50 a month on monthly billing: $199 for 350 plus 50 extras at $0.55.

Does sending.ac refund?

As a rule, no: its terms make subscription, domain and setup fees non-refundable, partial months included, with exceptions for billing errors and a prolonged outage at its discretion.

What do 2,500 cold emails a day cost with sending.ac?

625 Azure inboxes at 4 a day on Growth ($350.25) and Instantly Hypergrowth ($97): from $447.25 a month before domains. 100 Outreach2day mailboxes send the same for $171.67 with domains, warmup and our sequencer.

Related

More on sending.ac

Deliverability call

Talk to our deliverability team

Book a call with the people who run our mailbox infrastructure. We look at your current setup and tell you what to change. Mailboxes are $1.50 from 100 and $0.50 from 1,000; for larger volumes we size an Enterprise plan with you.

  • Review your domains, DNS records and current inbox placement
  • Size the setup: domains, mailboxes per domain and daily volume per mailbox
  • Plan warmup and the move from your current provider or sequencer
  • Larger volumes: the Enterprise plan and its price for your setup

Free call

See open times in your time zone and book on this page.

Or open the booking page

Sources

Each vendor's own pages. Vendors change prices and plans; if something here is out of date, write to support@outreach2day.com and we will fix it.

sending.ac
Outreach2day

Full volume from day 14: 25 cold emails a mailbox a day

Add domains, create mailboxes and turn on warmup. You see every mailbox's warmup numbers from day one.

Book a call
Price 100 mailboxes