ZeroSettle vs LoopMessage: price, outbound rules and webhooks (2026)

How we compared ZeroSettle and LoopMessage

We compared ZeroSettle and LoopMessage on seven criteria, using each company's own public pages as of October 8, 2026: the price of a number that can message first, what daily caps count, rules for messaging first, webhook signing and retries, name and photo, channels and regions, and reliability and refunds. LoopMessage, which says it has operated since 2020, sells one API where "All channels operate under the same phone number": iMessage, SMS/RCS and WhatsApp.

More vendors are on the iMessage API comparisons hub and in our comparison of 14 iMessage APIs and alternatives.

ZeroSettle vs LoopMessage at a glance

ZeroSettle and LoopMessage differ most on price, on what their caps count, and on webhook security.

Derived totals are our arithmetic from LoopMessage's listed prices; confirm at checkout. ZeroSettle cells come from its API docs, homepage and iMessage API Terms.

What does a number that can message first cost?

A ZeroSettle phone number that can message first is the Pro plan at $49 a month. On LoopMessage it takes the Light plan plus LoopMessage's phone-number and Init conversations add-ons: $104.99 a month plus $60 once, by our arithmetic from LoopMessage's pricing page as of October 8, 2026.

Over the first 12 months, once-off fees included, that is $1,319.88 on LoopMessage against $588 on ZeroSettle Pro (our arithmetic). Light is priced "from $59.99", so LoopMessage's total is a floor. ZeroSettle Pro has "No setup fee · Cancel anytime", unlimited messages with people who message you first, and 1,000 AI credits a month for the hosted agent; Growth, with 3+ numbers, is from $599/mo. ZeroSettle numbers can sell out, and then you join a waitlist. $49 buys no SMS fallback or WhatsApp. See iMessage API pricing compared and ZeroSettle's plans.

How do daily caps work?

LoopMessage caps unique contacts per sender per rolling 24 hours, including people you reply to. ZeroSettle's daily cap counts only new contacts, the people your number messages first, and never limits anyone who texted the line first.

LoopMessage: Light covers 300 and Regular 1,000. Its help center says "You can respond to contacts immediately, within your unique daily contact limit," and at the cap: "You will still be able to receive inbound messages, but you will not be able to reply." The same article describes a monthly unique-contact cap too, using 300 a day and 1,000 a month as its example; the pricing page lists only the daily figures.

ZeroSettle: Pro allows 5 new contacts a day per number (3 AM to 3 AM Eastern); Growth allows 50 a day and 3 per 15 minutes per number. Both allow at most 2 unanswered messages to a contact until they reply. The docs define a new contact as "a handle the line delivers a text, voice message, or photo to first; reactions, typing, profile shares, and failed sends never count."

Limit math: 400 people text an AI assistant in one day

Say 400 people text an AI assistant's number in one day, and the assistant also messages first 15 people who asked for a text on a web form. The figures below are our arithmetic from each vendor's published limits.

• LoopMessage Light: 415 unique contacts is over the 300 cap, so about 115 people get no reply until earlier contacts age out of the rolling 24 hours. Regular (1,000) covers the day at $144.99 a month plus $60 once with a phone number and Init. The 15 first messages fit the ramp-up only from its 7–14-day step (20 a day), sent about 15 minutes apart.
• ZeroSettle Pro: all 400 get answers, because people who texted first are never limited. The 15 first messages don't fit under 5 a day: the first 5 go out, the 6th returns 429 new_contact_limit with retry_after_s, and the other 10 wait for the next two days (or need Growth, at 50 a day per number). Replies from your own server use no AI credits; if the hosted agent answers instead, one text to each of the 400 uses 400 of Pro's 1,000 monthly credits.

What does messaging first require?

LoopMessage requires the Init conversations add-on, a ramp-up period that starts at 2 new conversations a day, a reply rate "over ~30%" and a "~15 minute interval" between new conversations. ZeroSettle requires no add-on and publishes no ramp-up schedule: the plan's new-contact limits apply from the first day. Both require consent: LoopMessage's pricing FAQ asks for a contact who "has recently opted-in or recently provided you consent", and ZeroSettle's docs say "If you are unsure whether you have consent, you don't." Consent rules vary by country; this isn't legal advice.

LoopMessage figures as published in its send-first article, which says they "are adjustable by individual request and depend on your reply rate". ZeroSettle's limits are per number.

LoopMessage bars marketing, links, emails, phone numbers, currencies and attachments from a first message. ZeroSettle refuses photos and voice messages until the contact has replied (403 attachment_before_reply), and still sends a first message that contains a link but returns the warning link_not_tappable, because an iPhone shows links from an unknown sender as plain text until the recipient replies or saves the number. On both, open by asking for a reply.

Keeping a business iMessage number out of spam filters explains why these rules exist.

How do webhooks, branding and reliability compare?

ZeroSettle signs every webhook with HMAC-SHA256 and retries a failed delivery 3 times; LoopMessage authenticates webhooks with an authorization header you set and retries up to 30 times over about 3 hours. Neither company publishes an SLA.

Webhook signing and retries

A static header proves only that the caller knows your token. ZeroSettle's X-ZeroSettle-Signature: t=<unix>,v1=<hex> is an HMAC-SHA256 of "<t>." + raw body, so your server can also reject an altered body or a request over 300 seconds old. "typing_events": true adds inbound typing.started / typing.stopped, which LoopMessage's event list lacks.

import hmac, hashlib, time

def verify(secret: str, header: str, raw_body: bytes, tolerance: int = 300) -> bool:
    try:
        parts = dict(p.split("=", 1) for p in header.split(","))
        t, v1 = int(parts["t"]), parts["v1"]
    except Exception:
        return False
    if abs(time.time() - t) > tolerance:
        return False
    expected = hmac.new(secret.encode(), f"{t}.".encode() + raw_body, hashlib.sha256).hexdigest()
    return hmac.compare_digest(expected, v1)

LoopMessage's 30 retries (10 every 30 seconds, 10 every 3 minutes, 10 every 15 minutes) ride out a three-hour receiver outage. ZeroSettle retries after 1 s, 5 s and 20 s, then records the failure in last_delivery; after a longer outage, catch up with GET /api/imessage/messages?after_id=…. See ZeroSettle's webhook steps.

Name and photo

ZeroSettle shares your brand name (up to 64 characters) and photo automatically with the first message of every conversation; recipients see "<name> shared a name and photo with you". LoopMessage's help center recommends sending "a contact file vCard" as an attachment; recipients see your name and photo once they add it to their contacts.

Reliability evidence

ZeroSettle reports "99.9% uptime" on its homepage, a published stat rather than an SLA; its terms say ZeroSettle "does not warrant that the services will meet your requirements or that their operation will be uninterrupted or error-free". LoopMessage publishes no uptime figure; its status page lists a "Messaging performance issue" open from 12:30 UTC on May 31 to 03:20 UTC on June 1, 2026, and an "Issue with CDN provider" on June 4, 2026, from 20:00 to 22:00 UTC.

When ZeroSettle is not a fit and LoopMessage is the better choice

LoopMessage is the better choice when you need a channel, region, volume or feature ZeroSettle lacks (as of October 8, 2026).

• WhatsApp and SMS/RCS fallback on one number. ZeroSettle is iMessage only; SMS fallback is on its roadmap.
• More than 5 new conversations a day from one number. After 21 days, LoopMessage's schedule allows up to 50 a day per sender, depending on reply rate. ZeroSettle Pro stops at 5; 50 a day per number is ZeroSettle Growth, from $599/mo.
• A non-US or ported number. UK numbers self-serve; Australia, Germany, New Zealand, Spain, Portugal and Japan on request with a local ID; US mobile numbers can be ported in. ZeroSettle's numbers "remain the property of ZeroSettle".
• More iMessage features. Sending to existing group chats (it can't create them), edit (15 minutes), unsend (2 minutes), effects, a message_delivered event and inbound voice transcription. ZeroSettle documents none of these.
• No-code and Twilio-style integrations: n8n, Zapier, Slack, Pipedream and HighLevel, plus a Twilio-compatible endpoint (LoopMessage says it "tried to maintain backward compatibility").
• A free or low-cost start. A $0 Sandbox for 5 contacts, or a $20/month shared sender for 50 monthly contacts, "Only for AI assistant use cases". ZeroSettle has no free trial.
• Long retries or your own storage: about 3 hours of webhook retries, and inbound files kept in "your S3 bucket or compatible service".

Neither vendor fits if you need a contractual SLA, and ZeroSettle's terms do not allow health information without a Business Associate Agreement. Whether your messages involve health information is a question for your counsel; this isn't legal advice.

When ZeroSettle is the better choice

ZeroSettle is the better choice when you want to message first from a phone number for one price, and nobody who texted you should go unanswered because of a cap.

• Price and limits: $49 a month on Pro, 5 new contacts a day per number from day one, and unlimited messages with people who message you first.
• Built in: signed webhooks, inbound typing events and an automatic name-and-photo card.
• A hosted AI agent: "Managed by AI Agent" (Beta) answers every inbound text from your business context, with no server to run; LoopMessage lists none.
• Refund and replacement: "ask within 30 days and you are refunded in full and the subscription is cancelled"; a flagged number is replaced "right away at no extra charge", with a new number but the same API token, webhook and code. LoopMessage's terms say paid subscription fees "cannot be pro-rated" on cancellation, and its help center calls senders blocked over recipient reports "non-refundable".

Get a ZeroSettle number or read the ZeroSettle API docs. See also what an iMessage API is and ZeroSettle vs Blooio.

How we checked

We read every LoopMessage page cited here (pricing, help center, API docs, terms and status page) on October 8, 2026, copied figures as published and labeled our own arithmetic. ZeroSettle facts come from its API docs, homepage and terms. We did not test a paid LoopMessage plan, so nothing here measures its delivery or speed. We re-check every LoopMessage figure each quarter and log changes below.