Airalo vs Holafly vs Nomad vs Saily: what an AI agent picks
There's no single winner. Airalo — deepest catalog, usually cheapest in Asia. Holafly — best unlimited-data plans. Nomad — often cheapest in Europe. Saily — competitive globally, bundles VPN. A neutral AI agent through cartapi picks by your criteria (cheapest $/GB, unlimited only, longest validity) instead of by affiliate margin. Every "best of" listicle you find on the internet is a Holafly affiliate blog or a solo travel blogger. This is neither.
Every "Airalo vs Holafly" article ranked in Google's top ten is written by a company that sells one of them. That's the problem. This article is written by someone who sells all four via an aggregator, has no incentive to prefer any of them, and can tell you which one an AI agent actually picks when you ask nicely.
The 30-second verdict
| Brand | Best for | Weak on |
|---|---|---|
| Airalo | Deepest catalog (200+ destinations), best price/GB in Asia, most-used tourist eSIM globally. | Europe pricing beaten by Nomad and eSIM-Go-adjacent providers. |
| Holafly | Unlimited-data plans in ~170 destinations. Strongest brand recognition among travelers. | Usually more expensive per equivalent GB; unlimited often includes soft throttling. |
| Nomad | Best price in a lot of Europe. Clean app. | Catalog thinner than Airalo. Fewer plan sizes per country. |
| Saily | Competitive globally. Bundles NordVPN's VPN. Backed by Nord Security. | Newer, smaller catalog. Fewer country-specific edge cases covered. |
Every one of those cells has counter-examples. Below is the detail.
Coverage: who sells where
All four cover the traveler-important destinations (US, EU, Japan, Thailand, Turkey, Mexico, Vietnam, Indonesia, Australia, UK). The differences show at the edges:
- China: Airalo, Holafly, Nomad all sell "China" eSIMs that actually route via Hong Kong or overseas gateways (bypassing the Great Firewall as a side effect). Saily has this too. Coverage and throttling behavior differ per plan — check each.
- Cuba: Airalo has an eSIM. The others don't (or didn't when I last checked).
- Regional bundles (Europe-wide, Asia-wide, Global): Airalo's "Discover" plans are the most flexible. Holafly does regional. Nomad does regional. Saily does global.
- Rural regions: coverage depends on which local carrier the aggregator has an MVNO deal with, not the aggregator brand. Same eSIM on the same carrier gives the same signal.
Pricing: normalized $/GB by region
Approximate 2026 medians from cartapi's normalized catalog. Real prices fluctuate — the agent quotes live at checkout.
| Region | Airalo | Holafly (unlimited baseline) | Nomad | Saily |
|---|---|---|---|---|
| Europe (regional) | ~$1.50/GB | ~$3/day unlimited | ~$1.20/GB | ~$1.40/GB |
| Japan | ~$1.60/GB | ~$3.50/day unlimited | ~$1.80/GB | ~$1.70/GB |
| Thailand | ~$1.20/GB | ~$3/day unlimited | ~$1.40/GB | ~$1.30/GB |
| USA | ~$2/GB | ~$4/day unlimited | ~$2.20/GB | ~$2/GB |
| Mexico | ~$1.80/GB | ~$3/day unlimited | ~$2/GB | ~$1.80/GB |
Holafly's model is different — you're paying for time (a day of unlimited), not a bucket. For heavy users (video calls, tethering) that math wins. For light users (Maps + WhatsApp) a $10 5GB pool is way cheaper.
Data policies: what "unlimited" and "throttling" actually mean
- Pooled data (Airalo, Nomad, Saily): you buy 5GB, when you use it it's gone. Simple. Overage plans available. No throttling until the pool ends.
- Unlimited with fair-use throttling (Holafly on many destinations): some destinations advertise "unlimited" but throttle after 500MB or 1GB per day, dropping speed to 128kbps–512kbps. Fine for maps and messaging; painful for video. Read the plan page.
- True unlimited (Holafly on some destinations, Airalo on select unlimited SKUs): no per-day cap, no throttle. Confirm in the plan detail before assuming.
"Unlimited" in eSIM-world is a marketing word, not a technical one. Every brand does it differently; every brand's fair-use policy is buried in fine print. When it matters, ask the agent to surface it:
using cartapi, get me a Japan eSIM. If unlimited, tell me the throttling policy before I buy.
Phone numbers: mostly a no
As of 2026, all four aggregators are overwhelmingly data-only for tourist eSIMs. If you need a real phone number:
- Airalo: has phone-number-included plans in a small set of destinations (US Discover-Number, Turkey). Not a general offering.
- Holafly, Nomad, Saily: data-only for the tourist product.
- For destination-specific SIM-number requirements (Japanese bank/wallet, Korean ekyc, some Chinese apps), a local operator's own eSIM is usually the answer, not any travel aggregator.
App UX, briefly
All four apps do the same job: buy, install QR, monitor usage, top up. Differences are aesthetic. Airalo has the most refined app because they have the most users; Nomad's is the cleanest; Saily's feels the most modern (Nord's design DNA); Holafly's is the busiest.
An AI-agent flow (cartapi) skips the app entirely — you get the QR by email, install it, and never open the aggregator's app unless you want to top up mid-trip.
Support, refunds, activation problems
Roughly comparable. All four have chat/email support with 24–48h response times. Airalo has the biggest support org. Refund policies converge on "we'll refund if the eSIM never activated, we won't if you burned through the data and want a do-over." Holafly's refund reputation on Reddit is spotty; Airalo's is average; Nomad and Saily are quieter, generally decent.
What a neutral AI agent picks
With cartapi's neutral catalog behind it, an agent picks purely on the criteria you stated. Ask for cheapest $/GB → probably Airalo or Nomad depending on region. Ask for unlimited → probably Holafly. Ask for longest validity per dollar → varies by country. Ask for lowest total price → whichever plan has the smallest bucket that meets your ask.
The unfair advantage of the neutral aggregator: no affiliate margin baked into the recommendation. The Holafly-branded blog will always recommend Holafly. The Airalo blog always recommends Airalo. A cartapi agent recommends whatever fits.
Try it
claude mcp add --transport http cartapi https://mcp.cartapi.io/mcpusing cartapi, compare the top 3 eSIMs for Japan (10GB, 10 days). Show provider, network, price, and $/GB.
The agent will list the plans side by side, with the winning provider not preordained.
Note on current coverage: cartapi's live eSIM adapters are Airalo and Nomad. Holafly and Saily are on the wholesale-integration roadmap. For today, the "neutral pick" surface is Airalo vs Nomad; the analysis above applies once all four are wired.
Frequently asked questions
Is Airalo, Holafly, Nomad, or Saily the best travel eSIM?
No single winner. Airalo — deepest catalog, cheapest per-GB in Asia. Holafly — unlimited plans. Nomad — often cheapest in Europe. Saily — competitive globally, bundles VPN. A neutral agent picks by your stated criteria.
Which provider has unlimited data?
Holafly is built around unlimited on most destinations. Airalo, Nomad, and Saily each have unlimited on a subset. "Unlimited" often includes throttling after a daily cap — always read plan detail.
Which provider supports a real phone number?
Mostly none — all four are overwhelmingly data-only for tourist eSIMs in 2026. Airalo has a small set of phone-number plans (US, Turkey). Destination-specific number requirements are best served by a local operator's eSIM.
Can I compare all four in one place?
Cartapi is a neutral catalog: Airalo and Nomad are live, Holafly and Saily are on the wholesale-integration roadmap. Where multiple providers are wired, the agent normalizes and returns the best match without affiliate bias.
Which is best for China?
All four route "China" eSIMs via HK/overseas gateways (they'll bypass the Great Firewall as a side effect). Coverage and throttling differ per plan; check the specific plan page. Airalo's is the most-battle-tested.