Introduction
Reliance Jio rocked the Indian telecommunication sector when it debuted in 2016. When people were shelling out hefty tariffs for voice calls and mobile data, Jio arrived with an aggressive plan—free voice calls, cheap as-chips data, and no roaming in India. From its activation process to its secret potential, the Jio SIM represented disruption and digital empowerment. Millions have used it, and many have yet to be told about all that their Jio SIM can really do.
Here in this article, we’re going deep into five surprising facts about Jio SIM cards — things that most users wouldn’t even know. If you’re an old Jio customer or just someone interested in making the switch, these facts will make you think differently about your SIM card.
Instant Activation Without Physical Verification
One of the most revolutionary things Jio did on launch was offering **instant SIM activation via Aadhaar-based eKYC**. Purchasing a new SIM card in India previously involved filling out long physical forms, providing photocopies of ID/address proof, and waiting anywhere from 24–48 hours for activation. It was slow, laborious, and prone to errors.
Jio flipped the script by allowing users to activate their SIM cards in a matter of minutes—all through biometric verification linked to their Aadhaar number.
However, this innovation also gave rise to controversies regarding privacy and security. Associating SIM cards with biometric information raised the question of data misuse and surveillance. Although the government subsequently imposed stricter checks on the use of Aadhaar, Jio’s eKYC launch was undoubtedly a first in Indian telecom history—and an obvious indicator of how it intended to reinvent user experience from the very beginning.
Pre-enabled VoLTE Technology on All Jio SIMs
VoLTE, short for Voice over LTE, is a technology that enables voice calls to be made using a 4G LTE data network rather than reverting to previous-generation 2G or 3G networks. This is significant because it provides crystal-clear HD voice quality, quicker call setup, and high-speed internet. In contrast, on a call — all of which were major holdbacks on previous networks.
Right from the start, each Jio SIM card was pre-enabled with VoLTE support, which is another leap ahead. When Jio launched, the majority of Indian telecom operators still used 2G/3G networks for voice calls and saved 4G for usage, mostly by data. This translated into frequent dropped calls, voice clarity problems, or delayed network switches when customers made both voice and data connections simultaneously.
Jio, in contrast, constructed its whole infrastructure as an all-IP 4G network so that there was no fallback to legacy—all calls, messages, and packets of data were routed over 4G. That enabled budget phones with Jio SIMs to provide HD voice clarity, with calls sounding as if both parties were in the same room.
Against the backdrop of traditional SIM cards that needed to be manually upgraded or were not VoLTE compatible, Jio’s out-of-the-box, seamless VoLTE experience created a new standard for the industry. It was not about quicker data — it was about an intelligent, smoother, and more contemporary communication experience for everyone, day one.
Free Jio SIM Cards with Massive Freebies at Launch
When Jio entered the scene in 2016, it did not merely enter the marketplace — it shattered it. Its most staggering act was giving away totally free Jio SIM cards with unlimited voice calls, data, SMS, and application access for months with its “Welcome Offer” and then the “Happy New Year” plan. Customers would be able to enter a shop, receive a free SIM activated in minutes, and get going on fast 4G data and calling — without spending a rupee.
This zero-cost entry strategy, aggressively pursued, was unprecedented in India’s telecom industry, where even SIM cards typically had an activation fee attached and restricted benefits. By eliminating the cost barrier and inundating the market with free services, Jio quickly acquired more than 100 million customers within less than 6 months — a feat no operator ever pulled off so quickly.
The shockwave struck the rivals hard. Industry giants such as Airtel, Vodafone, and Idea (now Vi) had to cut their data prices, launch unlimited call packs, and speed up their 4G rollouts to remain solvent. Jio not only acquired users but changed the game of telecom economics in India.
For customers, it was too good to be true — fast internet, streaming apps for free, and crystal-clear calls, all without the need to spend a rupee. What started as a “limited-time trial” quickly became a new permanent reality in consumer expectations. Millions of Indians experienced the authentic taste of digital India for the first time through a free Jio SIM, and they never turned back.
Hidden USSD Codes Unlocking Extra Features
USSD codes are rapid, dialable codes that allow you to retrieve different telecom services from your phone’s keypad, even without an internet link. They typically begin with a * and terminate with a # and are processed in real time via your network operator’s system.
While most Jio users rely on the MyJio app for checking balances, data usage, and offers, not everyone knows that Jio also supports several hidden USSD codes that unlock useful features instantly — especially handy if you’re using a basic phone or have limited data access.
Here are some of the most valuable and lesser-known Jio USSD codes:
- *333# – Check your principal balance and validity instantly.
- *1# – Retrieve your Jio number (handy if you’re on a new SIM).
- 1299 (Toll-free) – Hear your data and voice usage details through IVR.
- 1991 – Recharge or find information about active plans (also accessible through IVR).
- *#06# – Shows your device’s IMEI number (accessible on all SIMs).
- *789# or *123# – Might show alternate offers or bonus balances (operational in certain regions).
These shortcuts prove particularly useful when connectivity is bad or when people do not wish to install apps. They provide instant access to crucial account details without the need to wait for SMS responses or loading.
For those on the move, using feature phones, or who want a quick way of accessing information, USSD codes provide a potent, underappreciated alternative. Having them at your fingertips puts you in greater command of your Jio SIM—no app, no delay, just results.
Conclusion
Jio didn’t just launch a SIM card, it launched a revolution in the Indian telecom space. From the moment it entered the market, Jio challenged outdated systems and raised the bar for what users could expect from a mobile service provider.
Let’s quickly recap the five shocking facts about Jio SIM cards:
- Instant Activation Without Physical Documents – Aadhaar-based eKYC made SIM activation fast, paperless, and seamless.
- Pre-Enabled VoLTE Technology – Every Jio SIM supported HD voice calls over 4G from day one, giving users a next-gen call experience.
- Free SIMs and Services at Launch – Jio gave away millions of SIM cards along with free data and calls, disrupting the entire telecom market.
- Built-in 5G Compatibility—You don’t need to change your SIM to use Jio’s blazing-fast 5G, provided you have a compatible phone.
- Hidden USSD Codes for Quick Access – Powerful, lesser-known shortcuts allow users to manage their Jio account without even opening an app.
FAQs
- Do I have to provide documents to activate a Jio SIM?
No, if you choose Aadhaar-based eKYC at the retail outlet, your Jio SIM can be activated immediately without submitting any documents.
- Is VoLTE on all Jio SIM cards?
Yes, all Jio SIMs are VoLTE-enabled as standard, enabling HD voice calls on 4G without any extra work.
- Can I still avail of a free Jio SIM card?
Though free SIM launch offers are no longer available, Jio SIM cards remain inexpensive or come with recharge plans in most instances.
- Will my Jio SIM work with 5G?
Yes, Jio SIMs are already compatible with Jio’s 5G network. No SIM upgrade is required — just a 5G-supported phone and coverage area.
- How can Jio’s balance be checked without using the MyJio app?
Type *333# on your Jio number to see your principal balance immediately.
- What is USSD to know my Jio number?
Type *1# to show your Jio number on the screen.
- Can I use my Jio SIM in a 3G phone?
No, Jio SIMs are used only in 4G or 5G-compatible handsets, as the network does not support 2G or 3G technologies.
- How fast is Jio’s 5G network?
Jio’s standalone 5G network offers up to 1 Gbps speeds, although actual speeds depend on where you are and what phone you’re using.
- Is there a secret fee for using USSD codes?
No, USSD code use is unrestricted and does not need a data connection.
- Can I continue to use my existing Jio SIM with a new 5G phone?
Yes. Just place your current Jio SIM in a 5G device, and it will automatically get connected to the 5G network.
