The United States is one of the few rich countries where arriving with no data plan is genuinely awkward. Unlike Bangkok or Istanbul, US airports have almost no SIM-card counters — the expectation is that you already have service. Carrier retail stores exist in every city, but prepaid activation there typically wants a US ZIP code, adds state taxes and fees at the register, and eats an hour of your first day. That retail gap is a big part of why eSIMs became the default way for visitors to get online in the US.
This guide compares every realistic option for someone landing at JFK, LAX, MIA or SFO with an eSIM-capable phone. The benchmark throughout is the Roamzy per-MB rate for the United States — $0.0032/MB (~$3.28/GB) — used as a measuring stick, not a sales pitch. Where a competitor wins, we say so.
Quick map: your options on arrival in the US
- Carrier prepaid at a retail store — T-Mobile and AT&T prepaid run $45-65/month advertised, before taxes and fees. Solid product, but it's a monthly plan sized for residents, requires a store visit, and the counter process (ID, ZIP code, activation kit) is the slowest option on this list.
- T-Mobile U.S. Pass eSIM — a visitor-oriented pass: 7-30 day options advertised at $25-50 as of mid-2026, with the top tier advertised with tens of gigabytes of data plus voice and text. Arguably the strongest carrier-direct option the US has offered tourists — but it's designed to be activated once you're in the US.
- Traveler eSIM packs — Airalo's US plans are advertised from about $6 (1 GB) up to $42-59 (50 GB); Saily advertises 3 GB for $8.99. Fixed allowance, 30-day expiry, unused data forfeited.
- "Unlimited" eSIM — Holafly's specialty, advertised around $3-4/day for the US (per-day price drops on longer plans). Genuinely unlimited on-device browsing, but their own fair-use terms allow operators to reduce speeds after heavy daily use, and hotspot data is capped separately.
- Per-MB global eSIM (Roamzy and similar) — top up a balance in USDT/USDC, the meter ticks at $0.0032/MB while you're on a US network. No pack to size, no expiry on the balance, same eSIM works in 193 countries.
Ten-day US trip — the cost table
Same itinerary priced through each option. Profile: 10 days, ~150 MB/day of cellular use (Maps navigation, messaging, ride-hailing, photo uploads, restaurant lookups), hotel or Airbnb WiFi at night. That's ~1.5 GB total — a realistic tourist number; see how much data you actually need for the breakdown.
| Option | Total cost (10 days) | What you actually get |
|---|---|---|
| T-Mobile/AT&T prepaid (store) | $45-65 advertised + tax | A full monthly resident plan for a 10-day visit. Includes a US number. Store visit required. |
| T-Mobile U.S. Pass eSIM | $25-35 advertised | 7-14 day pass, generous data, voice and text included. Best-in-class if you want a US number — but designed to be activated after you land. |
| Airalo US 5 GB / 30 days | $13-16 advertised | 5 GB pack. You'll use ~1.5 GB and forfeit the rest at expiry. |
| Saily US 3 GB / 30 days | $8.99 advertised | Tighter pack, less waste. Still ~1.5 GB paid for and unused. |
| Holafly "unlimited" 10 days | $34-38 advertised | Unlimited on-device with fair-use speed reductions after heavy daily use; hotspot capped separately. |
| Roamzy per-MB | ~$5 (1.5 GB × $3.28/GB) | Pay only for the megabytes used. Leftover balance never expires — it just waits for your next trip, any country. |
When per-MB stops winning in the US
Three scenarios where the honest answer is "buy something else":
- You stream on cellular. An hour of HD video is ~1-3 GB. At $0.0032/MB one Netflix episode on the interstate costs $3-10. If cellular streaming is your plan, Holafly's daily-fee model or T-Mobile's U.S. Pass wins outright.
- You're staying a month or longer. Above roughly 12-15 GB/month, a $40-50 carrier prepaid plan beats per-MB on pure cost — and adds a US number for two-factor codes from US services.
- You work full-time on hotspot. Video calls run ~500-700 MB/hour. Even one hotspot video call a day adds 7-10 GB over two weeks; a full-call-schedule remote worker blows far past that. Run the comparison both ways before choosing.
Rule of thumb: under ~5 GB in two weeks, per-MB wins comfortably; above it, packs and carrier plans deserve a serious look.
Coverage reality: cities are easy, road trips are not
The US has three national networks — Verizon, AT&T, T-Mobile — and in every tourist city (New York, LA, Miami, Vegas, Chicago, San Francisco) all three deliver fast 5G that's effectively indistinguishable. The differences appear when you leave the metro:
- Verizon has historically the deepest rural footprint — the carrier most associated with having signal "in the middle of nowhere" and along remote interstate stretches.
- AT&T is a close second on rural corridors, with strong metro 5G.
- T-Mobile leads on mid-band 5G speed in cities but is the one you're most likely to lose on empty two-lane highways in the Mountain West.
Two things every road-tripper should internalize. First, major interstates (I-95, I-80, I-10, I-5) have near-continuous coverage on all networks. Second, national parks and desert stretches have genuine dead zones on every carrier — Big Bend, stretches of Utah's Highway 12, large parts of Death Valley and Yellowstone's interior have no signal, period. No eSIM fixes that; download offline maps before you leave pavement. (Carriers have started plugging these gaps with satellite messaging, but that covers texts, not data — for road-trip data, dead zones are still dead as of mid-2026.)
Roamzy attaches to available partner networks in the US and the phone uses the strongest signal at your location; in cities you won't be able to tell the difference. A useful per-MB side effect on road trips: driving days are mostly navigation and music-you-downloaded, so they're cheap days — you're not burning a fixed daily fee while your phone does almost nothing.
USA + Mexico + Canada on one eSIM
Combined itineraries — LA plus Baja, New York plus Toronto, a full PCH-to-Vancouver run — are where the single-eSIM model pulls furthest ahead. Pack providers sell separate country plans or a "North America regional" pack (Saily advertises regional plans from $3.89); either way you're pre-guessing how your data splits across borders, and the expiry clock spans all three countries.
With one global per-MB eSIM there is nothing to plan: cross into Mexico or Canada and the meter simply switches to that country's published rate. No second QR code, no second expiry, no leftover gigabytes stranded in the wrong country's pack. Current rates for the neighbors are on the Mexico country page and the Canada country page, alongside the United States page.
No US ZIP code, no ID, no card games
Two friction points specific to the US market. Carrier prepaid activation usually asks for a US address or ZIP code — solvable with your hotel's, but one more small lie in the process. And foreign cards are declined at US self-checkout and online carrier flows often enough to be a running travel joke.
Roamzy sidesteps both by design: no account, no KYC, no address form. You pay in USDT or USDC, the QR code appears, done — the whole flow is anonymous. If you already hold stablecoins this is the shortest path from landing to online that exists; the mechanics are in the crypto eSIM guide. The honest caveat: if you don't hold crypto and don't want to, a card-based provider is simpler for you — this advantage is real but not universal.
One more thing US-specific: Roamzy is data-only — no US phone number, no SMS, no calls. Fine for WhatsApp, Maps, Uber and iMessage; not fine if a US service insists on texting a US number. For a short trip that's rarely an issue, but it's the one box the T-Mobile U.S. Pass ticks that no data-only eSIM can.
Bottom line for the US
For a typical one-to-three-week visit — navigation, messaging, uploads, WiFi at night — per-MB is the cheapest realistic option, typically by a factor of two to seven, and it's the only one that also covers a Mexico or Canada leg with zero extra setup. T-Mobile's U.S. Pass is the strongest carrier-direct product for visitors and wins if you need a US number or plan to stream heavily on cellular. Packs sit in the middle: fine per-GB prices if you exhaust them, quietly expensive if you don't.
Live per-MB rates for the US and 192 other countries are on the price page; the United States country page has the current rate and setup flow.
FAQ
Does one Roamzy eSIM cover the USA, Mexico and Canada?
Yes. The same eSIM works in all 193 covered countries; crossing a border just switches the meter to that country's per-MB rate. See the Mexico and Canada pages for their current rates.
Which US network will my eSIM connect to?
Roamzy attaches to available partner networks in the US, and your phone picks the strongest signal at your location. In tourist cities all major networks perform excellently; in remote areas, expect dead zones on every carrier and download offline maps.
Do I need ID or a US address to get connected?
Not with a per-MB eSIM: no account, no KYC, no ZIP code — pay in USDT/USDC and scan the QR. Carrier prepaid at a retail store typically involves ID and a US address for activation.
Is per-MB cheaper than an unlimited eSIM for the US?
For typical tourist usage (1-2 GB per week), yes — around $5 for a 10-day trip versus $34-38 advertised for 10 unlimited days. If you stream video on cellular daily, the unlimited model wins; the crossover sits near 5 GB of usage in two weeks.