The Samsung Galaxy S21 series launched in 2021 and remains widely used in India in 2026 — available at significantly reduced prices, making it one of the most popular secondhand flagship choices. And yes, the S21 fully supports eSIM technology.
Whether you bought your eSIM on Samsung Galaxy S21 new, refurbished, or secondhand, setting up an eSIM is straightforward and takes less than 10 minutes. This guide covers everything you need — from checking compatibility to activating with Jio, Airtel, and Vi, managing dual SIM, and fixing common issues specific to the S21 series.
- Check now – Does Samsung S21 Ultra Support eSIM?
Does Samsung Galaxy S21 Support eSIM?
Yes — the Samsung Galaxy S21, S21+, and S21 Ultra all support eSIM. However, two important conditions apply:
Condition 1 — Model variant:
The S21 sold in India and most global markets supports eSIM. However:
- China domestic variants — eSIM not supported
- Some US carrier-locked models — eSIM may be disabled
- India variant (SM-G991B/DS, SM-G996B/DS, SM-G998B/DS) — fully supported
Condition 2 — Software version:
The S21 must be running One UI 3.1 or higher for full eSIM support. Update to the latest One UI before activating.
How to Confirm eSIM Support on S21
Method 1 — Dial code:
Dial *#06# — if an EID number appears alongside IMEI numbers, eSIM is supported.
Method 2 — Settings check:
Settings → Connections → SIM Card Manager → If the Add mobile plan or Add eSIM option appears, the phone is ready.
Samsung Galaxy S21 eSIM Model Compatibility
| Model | eSIM Support | India Variant |
|---|---|---|
| Galaxy S21 (SM-G991B) | ✅ Yes | ✅ Fully supported |
| Galaxy S21+ (SM-G996B) | ✅ Yes | ✅ Fully supported |
| Galaxy S21 Ultra (SM-G998B) | ✅ Yes | ✅ Fully supported |
| Galaxy S21 FE (SM-G990B) | ✅ Yes | ✅ Fully supported |
| S21 China variant | ❌ No | N/A |
| S21 US carrier-locked | ⚠️ Check | Varies |
Indian Carriers Supporting eSIM on Galaxy S21
| Carrier | eSIM Support | Activation Method |
|---|---|---|
| Jio | ✅ Yes | MyJio app or SMS |
| Airtel | ✅ Yes | Airtel Thanks app or store |
| Vi (Vodafone Idea) | ✅ Yes | Vi app or store |
| BSNL | ⚠️ Limited | Store visit required |
Before You Activate eSIM on S21
Checklist before starting:
- ✅ Stable Wi-Fi — required during profile download
- ✅ One UI updated — Settings → Software Update → install all pending updates
- ✅ QR code ready — from carrier app, email, or store visit
- ✅ Phone unlocked — carrier-locked S21 may reject eSIM profiles
- ✅ EID confirmed — dial *#06# to verify eSIM support
- ✅ Active SIM with signal — OTP verification sent to registered number
Where to Find SIM Settings on Galaxy S21 (One UI 3/4)
The S21 runs One UI 3 or 4 depending on software version. SIM Manager location:
One UI 4 (Android 12):
Settings → Connections → SIM Card Manager
One UI 3.1 (Android 11):
Settings → Connections → SIM Card Manager
Note: Samsung renamed “SIM Card Manager” to “SIM Manager” in One UI 5 (S22 series onward). On S21, it is always called SIM Card Manager.
How to Activate eSIM on Samsung Galaxy S21 — All Methods
Method 1: QR Code Activation (Recommended)
Samsung Galaxy S21 standard method — works with all Indian carriers:
- Open Settings
- Tap Connections
- Tap SIM Card Manager
- Tap Add mobile plan
- Select Scan carrier QR code
- Point the S21 camera at the QR code from the carrier
- Tap Confirm when profile details appear
- Wait 30–60 seconds for download and installation
- Tap Done
eSIM now appears in SIM Card Manager alongside physical SIM.
Method 2: Activation Code (Manual Entry)
Use when QR code is on same device being activated:
- Settings → Connections → SIM Card Manager
- Tap Add mobile plan
- Select Enter activation code
- Type or paste code from carrier
- Confirm and wait for profile installation
Method 3: Jio eSIM Activation on S21
Via MyJio App:
- Open MyJio app
- Go to My Account → Get eSIM
- Verify with OTP sent to Jio number
- Follow in-app instructions
- eSIM profile pushed directly to S21
Via SMS:
- Send “SIMCHG <last 15 digits of EID>” to 199 from Jio number
- Reply 1 to confirm
- Receive QR code via SMS or email
- Scan using Method 1
Via Jio Store:
Visit nearest Jio store with S21 and Aadhaar card — activation takes 10–15 minutes.
Method 4: Airtel eSIM Activation on S21
Via Airtel Thanks App:
- Open Airtel Thanks app
- Account → My Plan → Manage → Switch to eSIM
- Verify with OTP
- Select Scan QR or let app push profile directly
- Follow completion steps
Via Airtel Store:
Visit Airtel store with S21 and valid ID — representative activates on spot.
Method 5: Vi eSIM Activation on S21
Via Vi App:
- Open Vi app
- My Account → SIM Services → Get eSIM
- Verify identity with OTP
- Follow in-app activation steps
Via Vi Store:
Visit Vi store with Aadhaar and registered number for in-person activation.
Setting Up Dual SIM on Samsung Galaxy S21
S21 supports one physical nano-SIM + one eSIM simultaneously.
Configure After Activation
- Settings → Connections → SIM Card Manager
- Both SIMs appear — rename each:
- Tap physical SIM → rename (e.g., “Jio Personal”)
- Tap eSIM → rename (e.g., “Airtel Work”)
Set Default SIM Preferences
Calls:
- Choose default call SIM
- Or select Always ask — S21 prompts which SIM per call
SMS:
- Select primary messaging SIM
Mobile Data:
- Choose one SIM for internet
- Switch anytime from quick settings or SIM Card Manager
Best Dual SIM Setups for Indian S21 Users
Setup 1 — Personal + Work:
- Physical SIM: Jio (personal calls + data)
- eSIM: Airtel (work number)
Setup 2 — Best of Both Networks:
- Physical SIM: Airtel (better voice quality)
- eSIM: Jio (better 4G/5G data speeds)
Setup 3 — Travel Setup:
- Physical SIM: Primary Indian number (always active)
- eSIM: International travel plan (Airalo/Nomad — download before travel)
Setup 4 — Data Optimization:
- Physical SIM: Primary number
- eSIM: Cheaper data-only plan for heavy internet usage
One UI 3 vs One UI 4 — eSIM Differences on S21
| Feature | One UI 3.1 (Android 11) | One UI 4 (Android 12) |
|---|---|---|
| Menu name | SIM Card Manager | SIM Card Manager |
| Add eSIM option | Add mobile plan | Add mobile plan |
| eSIM profile management | Basic | Improved |
| Always-On VPN | ✅ Supported | ✅ Supported |
| Quick settings toggle | ❌ | ❌ |
Recommendation: Update S21 to One UI 4 (Android 12) minimum before eSIM activation. One UI 4 improved eSIM stability and the SIM Card Manager interface significantly over One UI 3.
Managing eSIM Profiles on S21
S21 can store multiple eSIM profiles but activates only one at a time alongside a physical SIM.
Switch Between Stored Profiles
- Settings → Connections → SIM Card Manager
- Tap eSIM profiles
- Select profile to activate
- Tap Enable
- Confirm — wait 1–2 minutes for network registration
Useful for travelers who download country-specific eSIM plans and switch as needed.
How to Delete eSIM on S21
- Settings → Connections → SIM Card Manager
- Tap the active eSIM
- Tap Delete eSIM profile
- Confirm deletion
Important: Deletion is permanent on device. Contact carrier to re-issue before deleting paid plans. Your number and plan remain active — only the device profile is deleted.
S21-Specific eSIM Considerations
Battery and Performance
The S21 is older hardware — running dual SIM (physical + eSIM) simultaneously increases radio activity slightly. On the S21 (Exynos variant sold in India), this has a minor battery impact. To minimize:
- Set one SIM for data only, other for calls only — reduces simultaneous network scanning
- Disable eSIM when not in use if running on battery
5G and eSIM on S21
The S21 supports 5G — but India’s 5G rollout was primarily on Jio and Airtel bands that the S21 may not fully support depending on the variant. Check:
- Settings → Connections → Mobile Networks → Network mode
- If the 5G/LTE/3G/2G auto option appears, 5G capable
- Physical SIM and eSIM both support whatever network mode is available
Secondhand S21 eSIM Considerations
If you bought a secondhand S21:
- Check EID first — dial *#06# to confirm eSIM hardware is present
- Check if previous owner deleted eSIM profiles — SIM Card Manager should show no active eSIM profiles
- Factory reset recommended — ensures clean state before adding new eSIM
- Verify phone is unlocked — carrier-locked secondhand S21 may reject eSIM profiles
Common eSIM Problems on Samsung S21 and Fixes
“Add mobile plan” option not visible
Fix 1: Update One UI — Settings → Software Update → check for updates.
Fix 2: Dial *#06# — confirm EID appears. No EID = your S21 variant does not support eSIM.
Fix 3: Phone may be carrier-locked — contact original seller or carrier to unlock.
QR code scan fails on S21.
Fix: Clean rear camera lens. Ensure QR code display is at maximum brightness. Move to better lighting. Try manual activation code as alternative.
eSIM shows “Not activated” after download
Fix: Restart S21 after installation. Go to SIM Card Manager → tap eSIM → toggle off and on. Wait 3 minutes for network registration.
Mobile data not working after eSIM activation.
Fix: Settings → Connections → SIM Card Manager → Mobile Data → confirm the correct SIM is selected. Check APN settings — carrier app usually configures automatically, but manual APN setup may be needed.
OTP not received during activation
Fix: Physical SIM must have active signal during eSIM activation. OTP goes to registered number via physical SIM — ensure signal is strong before starting activation.
S21 gets warm during eSIM activation
Fix: Normal during profile download — keep phone still on a good Wi-Fi connection. If phone gets too hot, wait 5 minutes and retry. Avoid activating eSIM while phone is charging.
eSIM activated but calls not working on eSIM number
Fix: Settings → Connections → SIM Card Manager → Calls → select eSIM as default or “Always ask”. Also check that call barring is not active on new eSIM — contact carrier if calls consistently fail.
“SIM not provisioned” error after eSIM activation.
Fix: This indicates carrier-side activation is incomplete. Contact carrier (Jio: 199, Airtel: 121, Vi: 199) — provide your EID and request them to re-push the eSIM profile.
Transferring eSIM to S21 from Another Phone
Switching to S21 from another device:
- Get your EID — dial *#06# on S21 and note the EID number
- Contact carrier — inform them you are switching devices to Galaxy S21
- Provide new EID — carrier deactivates old device eSIM and generates new QR code for S21’s EID
- Scan new QR code on S21 using Method 1 above
- Your number, plan, and balance remain unchanged — only device changes
Note: Cannot transfer eSIM profiles directly between phones. Carrier re-issuance required every time you change devices.
eSIM vs Physical SIM on Galaxy S21
| Feature | Physical SIM | eSIM |
|---|---|---|
| Move to another phone | ✅ Instant | ❌ Carrier re-issuance needed |
| Dual SIM capability | ✅ With eSIM | ✅ With physical SIM |
| Travel flexibility | ❌ Buy local SIM | ✅ Download plan instantly |
| Works if SIM tray lost | ❌ No | ✅ Yes |
| Risk of physical loss | ✅ Can lose SIM | ❌ Built into phone |
| Carrier switching speed | Slow (new physical SIM) | Fast (digital download) |
| India carrier support | ✅ Universal | ✅ Jio/Airtel/Vi |
Frequently Asked Questions
Can I use eSIM and physical SIM at the same time on S21?
Yes. Galaxy S21 supports one physical nano-SIM and one eSIM active simultaneously. Both receive calls and SMS — you choose which handles mobile data.
Does Galaxy S21 FE support eSIM?
Yes. The Galaxy S21 FE (Fan Edition) supports eSIM in India. Verify by dialing *#06# — EID confirms support.
Will my existing Jio or Airtel number work on S21 eSIM?
Yes. Both Jio and Airtel support converting existing numbers from physical SIM to eSIM on the S21. Your number, plan, and balance transfer completely.
My S21 was purchased in the US — willan Indian eSIM work?
Depends on model. Some US unlocked S21 variants support eSIM. US carrier-locked models may have eSIM disabled. Check EID via *#06# — if present, eSIM hardware is available. Contact original US carrier to unlock if locked.
What happens to eSIM if I factory reset my S21?
Factory reset permanently deletes all eSIM profiles. Before resetting, contact your carrier to arrange re-issuance. After reset, dial *#06# for a new EID and provide it to the carrier for a new QR code.
Can I use an international travel eSIM on S21 while keeping an Indian number?
Yes. Download an international eSIM (Airalo, Nomad, Holafly) to S21 alongside an Indian physical SIM. Keep the Indian SIM active for OTPs and banking — use the travel eSIM for local data abroad. Switch between stored profiles as needed.
Is eSIM activation free on S21 for Jio and Airtel?
Jio charges approximately ₹10–₹25 for eSIM issuance. Airtel charges a nominal SIM replacement fee. Vi charges vary by plan. Your existing recharge balance and plan remain unaffected.
Conclusion
The Samsung Galaxy S21 handles eSIM setup reliably — especially after updating to One UI 4. Whether you activate through QR code scanning, the MyJio or Airtel Thanks app, or visit a carrier store, the process takes under 10 minutes and works consistently on all three major Indian carriers.
The practical benefits are immediate — dual SIM without sacrificing the physical slot, instant carrier switching, and the ability to download international travel plans directly to your phone. For Indian users who bought an S21 secondhand, eSIM activation is one of the first things worth setting up.
Verify your EID first by dialing *#06#, update One UI to the latest version, connect to Wi-Fi, and you are ready to activate.