Before you start

A valid passport (the legal ID for foreigners registering a line — no DNI required by law)
An unlocked, eSIM- or SIM-compatible phone (GSM/LTE bands; Argentina uses standard 4G/5G)
A local address or hotel for context, plus a credit/debit card (some carrier stores and apps don't take cash)
WhatsApp installed — it's the default channel for activation help and for daily life in Argentina

Step-by-step

1
Land connected with an eSIM
Before you fly, buy a Holafly (runs on Claro's network) or Airalo (Movistar network) eSIM and install the QR-code profile, but only switch on data roaming once you land. This gives you maps, WhatsApp and transfers from minute one, so you're not hunting for a SIM at Ezeiza. Holafly sells unlimited-data day passes; Airalo sells GB bundles — pick based on how long until you'll get a local SIM.
Mobile appWho: You, before departure10 minutes to set up; active on arrivalHolafly from ~US$6-7/day on longer plans; Airalo ~US$5 for 1GB up to ~US$49 for 20GB/30 days
2
Pick a carrier
Argentina has three networks: Claro (widest national coverage, biggest data packs out of the box — best for value and for travel beyond the city), Movistar (easy to find, urban-friendly promos, remote activation by WhatsApp), and Personal/Telecom (most flexible short-term packs and the cleanest online eSIM). For Buenos Aires life all three are fine; for trips to Patagonia or the north, lean Claro. Note Ezeiza airport typically only has a Personal stand, so for Claro buy in the city.
OnlineWho: YouDecision; same day
3
Buy and register a prepaid SIM (the DNI-friction step)
Go to an official Claro/Movistar/Personal store with your passport and register the 'prepago' line on the spot — staff handle it in under ~10 minutes. This in-store route matters: a chip bought loose from a kiosco is built around the Argentine DNI 'numero de tramite' and frequently won't self-activate on a passport, which is the classic foreigner snag. Movistar can also activate remotely (send '#NOMI' via WhatsApp with a passport photo); Personal generally wants you in an office for a foreign passport. Expect the line to be set with a declared period of stay.
In personWho: You (with passport) at a carrier store~10-30 minutes in storeSIM chip is symbolic — roughly US$1-4
4
Top up and choose a data plan
Prepaid is pay-as-you-go: load credit ('carga virtual') with cash at any kiosco, pharmacy or supermarket showing a 'recarga aqui' sign, or by card in the carrier app, then buy a monthly data pack. Plans are cheap and almost all bundle unlimited WhatsApp and social apps. Roughly: Claro ~25GB/30 days for ~US$7-15, Movistar ~3-5GB for ~US$5-7, Personal short packs from ~US$1/day — exact USD shifts with the peso, so treat these as ranges.
Mobile appWho: YouMinutes; renew each cycle~US$5-15/month for a generous data + unlimited-WhatsApp pack
5
Wire up WhatsApp and the apps you'll actually use
Register WhatsApp on your new Argentine number — it's the backbone of communication here, used by landlords, banks, delivery, doctors and businesses, often instead of email or phone calls. Then add the essentials: Mercado Pago (payments/QR), a transit/maps app and SUBE info for the metro and buses, and your carrier's app (Mi Claro / Mi Movistar / Mi Personal) to track data and recharge.
Mobile appWho: You15-20 minutes

Documents you’ll need

Passport (mandatory ID for the line registration as a foreigner)
Credit or debit card (for stores/apps that don't accept cash, and for app top-ups)
Cash in pesos (for SIM purchase and kiosco 'carga virtual')
Local address or accommodation details (sometimes asked for the line record)

Things most newcomers don’t know

Buying a SIM is trivial; activating it on a passport is the real friction — and the fix is registering in person at an official carrier store, not a kiosco.

Since ENACOM's March 2025 rules, every line is tied to an identity validated against RENAPER, and local prepaid flows are designed around the Argentine DNI 'numero de tramite'. Foreigners are legally entitled to register with a passport, but the self-service/kiosco path often chokes on a non-DNI ID, so staff doing it at a store is what makes it actually work.

Source: ENACOM 'nuevos requisitos' (Mar 2025) + argentina.travel

An eSIM (Holafly or Airalo) is the easy answer for day one — install before you fly and you walk out of the airport already online.

It sidesteps the whole airport-SIM scramble and the activation hassle while you settle in, so you have maps, ride-hailing and WhatsApp immediately. Many travelers now just keep the eSIM and only get a local SIM if they need an Argentine number.

Source: Holafly; Airalo; solsalute.com

In Argentina, WhatsApp is infrastructure — not just chat. A working number that can run WhatsApp matters more than calls or SMS.

Landlords, banks, plumbers, clinics, delivery and shops all operate over WhatsApp, frequently instead of email or phone. That's also why every prepaid pack bundles unlimited WhatsApp.

Source: argentina.travel; solsalute.com

For coverage and value pick Claro; for short, flexible stays and the smoothest online eSIM pick Personal; Movistar is the easy-to-find middle.

Claro has the widest national footprint and the biggest data-for-money packs (key if you'll travel to Patagonia or the north), Personal sells daily/weekly packs and lets you buy/activate an eSIM online without a store. 5G is live in the Buenos Aires metro but still limited — 4G is the workhorse everywhere.

Source: Carrier comparisons; RCR Wireless (5G rollout)

Common mistakes to avoid

Buying a loose SIM from a kiosco and assuming it'll self-activate on your passport — it often won't; register in person at an official carrier store instead.
Counting on a Claro counter at Ezeiza — the airport generally only has Personal, so buy Claro in the city.
Showing up with only cash at a store or trying to top up by app without a card — some carrier points and apps don't take cash, while kioscos do.
Letting prepaid credit lapse past its 30-day window — your data (and eventually the number) can stop working; recharge before expiry, and remember a passport-registered line has a finite declared validity.

Make it your personal checklist

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