Does a one-person business need a phone system? The US arithmetic

For most one-person businesses in the US, no. You already pay for a mobile plan, and a $10-a-month virtual number turns the phone you carry into a business line that is not your personal number. That pair costs less over three years than the same mobile plan plus a seat on a phone system.

The seat starts earning its price the day a second person answers the phone, or the day you need an auto-attendant, call recording, or a desk phone. The crossover cases are listed at the bottom.

Every seat price on this site assumes a business that buys seats. This page is about the buyer one step earlier: one person, one phone, wondering whether the products in the main table are for them yet. The honest answer involves two prices most seat-versus-seat comparisons never mention — the mobile plan you keep paying either way, and the much smaller product that solves the actual problem.

The comparison is not seat versus nothing

The phone-system seat does not replace your mobile plan. A UCaaS app runs on the phone in your pocket, and the seat price buys the service, not the cellular connection under it — you keep paying your carrier regardless. So the real decision for one person is what to add on top of a mobile plan you already have:

The gap between the two adds is roughly $10 to $20 a month. Over this site's standard 36-month horizon, that is $360 to $720 — before fees, which fall mostly on the seat side, as what is not in the price sets out.

What the mobile plan half costs

The seven carriers below were checked on their own pricing pages on 2026-09-01. The pattern to read for is the same one the word "from" documents on software pricing: the number in large type is often an introductory rate, and the renewal price is the one you will actually pay in month thirteen.

Checked 2026-09-01 on each carrier's own pricing page. Lyca's plan-index prices did not render for our tooling; its figures are from individual plan pages.
CarrierAdvertisedWhat the page says happens next
Mint Mobile$15/mo, any planPrepaid 3/6/12-month terms ($45/$90/$180 upfront). 12-month Unlimited renews at $30/mo; 3-month Unlimited at $40/mo. "New customer offer applies to initial term only."
Twigby$5–$25/moIntro price for the first 3 months; 2GB then $15, 10GB then $25, Unlimited then $35
Visible$25/mo UnlimitedTaxes and fees included in the printed price. Annual option $275/yr
Ultra Mobile$25/mo UnlimitedRequires a 12-month prepay of $300, shown as a limited-time discount from $49 single-month. Taxes and fees extra
Lyca Mobile US"from $7.5/mo"Plan pages price a promo period with "ENROLLMENT IN AUTO-RENEWAL REQUIRED"; a 5% "regulatory recovery fee" applies to website purchases
PureTalk$24.99–$64.99/moFlat monthly prices, taxes and fees extra. The $54.99 tier includes a second phone number
T-Mobile (postpaid)$55–$65/lineEssentials Saver $55, Essentials $65; taxes and fees not included, and the page references $4.49/line in regulatory fees on some plans

Two rows deserve a sentence each. Visible is the only carrier of the seven whose printed price is stated to include taxes and fees, which makes it the only printed price on this table you can multiply by 36 without further research. And PureTalk's upper tiers bundle a second phone number into a carrier plan — a carrier selling the virtual-number layer directly, which is the clearest sign that this two-numbers-one-phone arrangement is an ordinary product now, not a workaround.

Does the arithmetic change over 36 months?

Not much — it mostly widens in favor of the smaller product. Take a concrete stack: Mint's 12-month Unlimited at its $30 renewal rate plus Google Voice Starter at $10 is $40 a month, about $1,440 over three years (plus the $15 intro months you start with). The same mobile plan plus an Ooma Essentials seat is $49.95 a month before taxes and fees, about $1,800 over three years, plus activation. The seat stack costs roughly $360 more and delivers an auto-attendant, ring groups and a desk-phone option that one person working alone may never switch on.

The place to check your own numbers is the calculator, which prices every published seat plan at one seat over the same horizon — and note that several providers in the table impose seat minimums that rule the one-person case out entirely, which is its own answer.

When the seat is the right answer

Only a few situations flip the arithmetic, but they flip it decisively:

If two or more of those describe the next twelve months, buy the seat now and read the seat-table page before choosing a tier.

Who this page is not for

This page is not for teams — at two people the seat products it argues against become the products it recommends, and the rest of this site prices them properly. It is also not for anyone whose business number must survive them selling the business: a number inside a personal carrier account is an asset entanglement a seat account avoids. And it is not advice about coverage, handsets or data speeds; the carrier rows above record prices and stated terms, nothing more.

Sources


Written by Kaz (pen name). Figures are copied from providers' published pricing pages on the dates shown. We have not used these products. Corrections: contact form.