The best US number for marketing agencies & their clients (2026)

I've run a small marketing agency for nine years, and the phone number problem never fully goes away. Every client wants a professional presence. Every campaign wants its own inbox so leads don't get muddled. And every quarter, somebody on the team is trying to receive a verification code for a US platform on a number that won't cooperate. For a long time we duct-taped this together with personal phones, one overworked Google Voice line, and a lot of "wait, which number did we give that client?" On a busy day it's a mess. On a bad day it's a leak — a lead texts a number nobody's watching, and you find out a week later.

So this is the piece I wish someone had handed me years ago: how an agency should actually think about US numbers — for itself and for every client it manages — and how to run several of them without the bill turning into another line item you have to defend.

Why an agency needs more than one number

If you manage other people's brands, one number does not cut it. Here's what mine are for, and probably what yours are too:

A professional +1 presence. A US number reads as a real business to a North American audience. It goes on the client's ads, their Google Business Profile, their WhatsApp — and it isn't somebody's personal mobile.
WhatsApp Business support and broadcasts. Most of the buying conversation happens in chat now. Each client's audience needs its own WhatsApp line so support threads, broadcasts and campaign replies stay under that brand, not mixed into a shared team phone.
Receiving OTP codes. Setting a client up on US tools — ad platforms, analytics, marketplaces — means catching verification codes. A dedicated number per client keeps those logins clean and handoff-ready.
Separation per client and per campaign. When a lead comes in, you want to know instantly which brand it belongs to. One number per client (or per big campaign) tells you that before you even read the message.

Add it up and a working agency needs five, ten, sometimes twenty numbers. Which is exactly where the usual "free number" apps fall apart.

Where the free apps let agencies down

Google Voice and TextNow get recommended constantly, and for a solo person sitting in the US they're fine. For an agency they're the wrong shape.

Both are North-America-only. Google Voice isn't offered outside the US, and TextNow blocks registration from outside the US and Canada. If your agency — or a contractor, or a client — is anywhere else in the world, you're locked out at the door. And even where they do work, they're built around one person, one number, one login. Provisioning a fresh line for each new client, keeping billing tidy, handing a number over when a client leaves — none of that is what those apps were designed for. You end up with a drawer of Google accounts and no clean way to manage any of it.

What I want from an agency number instead

Four things, and I'm not flexible on them:

I can buy it from anywhere, not just from inside the US.
It's cheap enough to run several without a finance conversation.
It's WhatsApp-ready and can grow into broadcasts when a client needs bulk marketing.
It receives OTP reliably so onboarding doesn't stall.

How G100 fits the agency use case

G100 (app.g100.us) is a US-registered app that sells dedicated US, Canada and Puerto Rico numbers, and — this is the part that matters for agencies with clients and staff spread around the map — you can buy from anywhere. No KYC, no document upload. You create an account, pick a number, it's live in minutes.

The pricing is what makes the multi-number model actually work. Each number is a flat $1.95/month — no contract, no annual lock-in. Run ten client lines and you're at under twenty dollars a month for the numbers themselves. It's pay-as-you-go from a USD wallet through Stripe, so you top up and draw down; calls are $0.03/min if you need to ring someone. That's a rate card you can absorb into a retainer without blinking. The full breakdown is on the pricing page.

Each number is WhatsApp-ready. Because the numbers receive SMS and calls, WhatsApp verification goes through — Meta sends the code, the number catches it, you register the client's line on WhatsApp Business. When a client is ready for real bulk marketing, there's an optional WhatsApp Business Cloud API add-on at $10/month that adds a shared inbox, broadcasts, message templates and automation. That's the piece that turns a support line into a proper campaign channel, and you only pay for it on the clients who need it.

It runs in the browser and on mobile, so a team member can watch a client's inbox from a laptop without juggling SIMs. And every number receives OTP, which is the quiet workhorse feature — half of agency onboarding is catching verification codes for something.

The honest caveat

I'd rather tell you now than have you find out mid-campaign: outbound SMS sending isn't live yet. The numbers receive SMS and OTP codes today, and voice calls work, but you can't send SMS blasts from them at the moment. For agency work this matters mostly if your plan was cold-SMS. If your bulk messaging lives on WhatsApp — which for most of my clients it does — you route that through the WhatsApp Business Cloud API add-on and you're covered. Just don't buy this expecting an SMS campaign tool today.

The comparison, side by side

Here's the short version, the way I'd put it in front of a client:

Feature	G100	Google Voice	TextNow
Available worldwide?	Yes — buy from anywhere	No — US only	No — US & Canada only
WhatsApp Business / broadcasts?	Yes — verify today; broadcasts via $10/mo Cloud API add-on	No	No
Cheap to run several?	Yes — flat $1.95/mo per number	Limited — one line per Google account	Limited — built for a single user
Receive OTP?	Yes	Yes (in the US)	Yes (in North America)

How I'd actually roll it out

If I were setting this up for an agency from scratch: one G100 number for the agency itself, then one per client as you sign them — put it on their WhatsApp Business, their profiles, their ad creatives. Tag each line by client name in your own notes so an inbound message is instantly identifiable. Turn on the Cloud API add-on only for clients doing real WhatsApp broadcasts, and leave everyone else on the flat $1.95 line. When a client leaves, you hand over or retire their number without unpicking a shared inbox. It's boring, and boring is exactly what you want from your phone infrastructure.

Grab your first number at app.g100.us, and check the pricing page for the full rate card before you scale up.

FAQ

Can my agency run a separate US number for every client?
Yes, and that's the whole point of using G100 for agency work. Each number is a flat $1.95/month with no contract, so a line per client or per campaign stays affordable. There's no KYC and you can buy from anywhere, so onboarding a new client's number takes minutes.

Does a G100 number work for WhatsApp Business and broadcasts?
Yes. G100's US and Canada numbers can receive the WhatsApp verification code, so you can register the number on WhatsApp Business. For bulk marketing — shared inbox, broadcasts, message templates and automation — there's an optional WhatsApp Business Cloud API add-on at $10/month per number.

Can we send SMS campaigns from a G100 number?
Not yet. The numbers receive SMS and OTP codes today, and voice calls work, but outbound SMS sending isn't live. For bulk messaging right now, run it through the WhatsApp Business Cloud API add-on rather than SMS.

Is a US number worth it if the client isn't American?
Often, yes. A +1 number reads as a professional business presence to a US or Canadian audience, and it's a clean way to receive OTP codes for US tools and platforms. G100 sells US, Canada and Puerto Rico numbers and you can buy them from anywhere, so an agency outside North America can still give a client a local-looking line.