eSIM Routing Explained: Where Your Traffic Actually Goes

Published: 14 hours ago (January 19, 2026 at 09:10 AM EST)

4 min read

Source: Dev.to

eSIM Infrastructure – What Happens After You Activate a Plan

The marketing is simple: “Local data in 190+ countries.”
You’d assume that means you get a local IP and traffic routes through the local carrier (e.g., connect in Germany → get a German IP).

Often that’s not what happens.

When you buy an eSIM you’re not getting a direct relationship with a local carrier; you’re buying access through a chain of intermediaries.

Typical Architecture

Your Device
   ↓
eSIM Profile (downloaded via SM‑DP+)
   ↓
Aggregator's Network Hub
   ↓
Wholesale Carrier Agreement
   ↓
Local Radio Access (the actual cell tower)
   ↓
Internet Breakout Point ← This is where it gets interesting

The internet breakout point determines where your traffic actually emerges, and it’s often not where you are.

Two Main Approaches Providers Use

Approach	How It Works	Pros	Cons
Local breakout	Traffic exits to the internet in the country you’re connected. You get a local IP, local latency, and everything behaves as expected.	Low latency, correct geolocation, fewer jurisdictional issues.	More complex & expensive for providers (needs agreements with every local carrier).
Hub routing	Traffic is sent back to a central hub (often in the Netherlands, Luxembourg, Singapore, etc.) before reaching the internet. You’re “connected” in Germany, but your IP says Amsterdam.	Cheaper & simpler for providers (single IX point to manage).	Added latency, possible mismatches in geolocation, jurisdictional exposure.

Why Hub Routing?

Cost – Maintaining one internet‑exchange point is cheaper than dozens.
Simplicity – Aggregators can manage traffic centrally.
Scalability – Easier to add new countries without renegotiating many carrier contracts.

How to Verify Your Own Connection

1. Check Your Public IP

curl -s ifconfig.me          # simple IP
# or
curl -s ipinfo.io

2. Get Detailed Geolocation

curl -s ipinfo.io/json | jq '{ip, city, region, country, org}'

3. Trace the Route

traceroute 8.8.8.8          # Linux/macOS
# or on Windows
tracert 8.8.8.8

If you’re physically in Germany but ipinfo.io reports the Netherlands, you have hub routing.

4. Compare Timezone vs. IP Location

# Device’s timezone
date +%Z

# IP‑reported timezone
curl -s ipinfo.io/timezone

A mismatch is a classic sign of hub routing.

When Does It Matter?

Use‑case	Impact of Hub Routing
Latency‑sensitive apps (video calls, gaming)	Extra 10‑20 ms (e.g., Frankfurt → Amsterdam → Internet) can be noticeable.
Platform trust (banking, streaming)	Inconsistent IP vs. timezone may trigger security flags or login challenges.
Jurisdiction	Traffic passing through a third‑country subjects it to that country’s legal framework – relevant for privacy‑focused users.
Content access (region‑locked services)	IP‑based geo‑checks may place you in the wrong region, blocking content.

For basic browsing the effect is usually negligible, but for the scenarios above it can be significant.

What Providers Actually Do

Provider	Transparency	Notes
Airalo, Holafly, etc.	Low – generic “local carrier partnerships” replies.	Marketing focuses on coverage, not routing.
Saily (Nord Security)	Low – bundles a VPN, but does not publish routing details.	VPN gives you control over apparent location.
VoidMob	High – publishes routing details and explains why it matters.	Smaller player, more open.

Why the Silence?

Complexity – Routing depends on carrier agreements, aggregator relationships, time of day, and network load.
Constant change – Providers switch aggregators, renegotiate deals, add carriers → documentation would need constant updates.
Competitive advantage – Infrastructure is part of the product; publishing it could help rivals.
Low user demand – Most travelers just want data that works; they rarely ask “where does my traffic go?”

These aren’t excuses, but they explain the industry‑wide lack of detail.

The Technical Details

eSIM profiles are provisioned via SM‑DP+ (Subscription Manager – Data Preparation). The profile holds authentication credentials but does not dictate routing.
Routing decisions happen at the aggregator level. Companies like BICS, Tata Communications, and others run the wholesale networks that connect eSIM providers to local carriers and decide where traffic breaks out.
Local carrier breakout requires a separate agreement with each carrier in each country – expensive and complex.
Hub routing is simpler: all traffic returns to a central point regardless of the radio connection location.
The GSMA eSIM specifications cover profile and provisioning standards, but say nothing about routing. That’s entirely up to the provider and its aggregator partners.

What to Do If Routing Matters for You

Ask before you buy – “Where does traffic terminate when I connect in [Country]?”
Test yourself – Use the commands above to verify IP, location, and latency.
Consider a bundled VPN – If the provider won’t give routing transparency, a VPN lets you control your apparent location.
Check documentation – Providers that publish routing info deserve credit for transparency.

Bottom Line

Most consumer‑focused eSIM providers prioritize coverage and price over routing transparency.
Hub routing is common because it’s cheaper and easier to manage, but it can add latency, cause geo‑mismatches, and expose your traffic to additional jurisdictions.
If you need predictable routing (for low latency, compliance, or content access), verify it yourself or choose a provider that openly shares its infrastructure details.

People, eSIM just works and routing doesn’t matter. But if you’re using it for work, accessing sensitive services, or just want to understand what you’re buying — now you know where to look.