Smart ID systems and OTPs are part of everyday digital life, but they can still feel confusing.
Put simply, a smart ID system acts like a digital identity card—it verifies who you are on websites and apps without making you fill out endless forms or remember complicated passwords. OTPs (One-Time Passwords), on the other hand, are those temporary codes sent to your phone or email when you’re logging in or confirming an action.
Together, Smart-ID and OTPs make logging in faster and safer. But you might still wonder what exactly they do, how they work, or why you keep receiving them. In this article, we’ll break it all down.
Picture by indra projects on Pexels
OTPs: What Are They & Why Do They Matter?
A one-time password (OTP) is a temporary, unique code used to authenticate a user for a single login session or transaction. Unlike traditional passwords, which can be reused and are prone to theft, OTPs expire after one use or within a short period, making them much more secure.
OTPs are mostly used as part of two-factor authentication (2FA) or multi-factor authentication (MFA), which adds an extra layer of security to prevent unauthorized access to accounts. Even if someone knows your password, they can’t log in without the OTP, which they won’t have access to.
OTPs are often delivered via SMS, email, or authenticator apps and are used across industries like banking, e-commerce, and corporate systems to protect sensitive transactions and accounts. There are two main types of OTP algorithms:
-
TOTP (Time-Based OTP): The code is generated based on the current time, and it’s valid for a set period (like 30 seconds). Common in apps like Google Authenticator or on hardware tokens.
-
HOTP (HMAC-Based OTP): This code is generated based on a counter or event (e.g., a specific transaction or login attempt). It remains valid until used or replaced by a new one. Often used in event-triggered systems.
Simply put, TOTP is like a countdown timer code, while HOTP is like a punch card—you use it once, then it’s done.
The security of OTPs lies in their temporary nature, preventing them from being reused or intercepted easily. For example, even if someone steals your password, the OTP acts as an additional security check, requiring a separate code to gain access.
However, OTPs are not without vulnerabilities. They can be intercepted through phishing or SIM-swapping attacks, which is why it’s important to keep devices secure and avoid sharing OTPs. Even with the risks, OTPs offer strong security in many different situations.
Enter the OTP Code Right! Your Contact Info Matters More Than You Think
When you’re asked to enter an OTP (One-Time Password), getting your contact info (phone or email) right is crucial. For instance, if your phone number or email isn’t correct, you could be locked out of your account.
To avoid these issues, make sure to include the correct country code when entering your phone number, and double-check your email for any typos. Use an email you’ll keep for a long time—avoid using temporary or work emails because losing access to them could make it harder to recover your account later.
Which Contact Information is Used for OTP Codes?
When you’re setting up or using Smart-ID and need to receive a one-time password (OTP), where that code is sent depends on how you registered your account.
If you used biometric registration (scanning your face or fingerprints), Smart-ID will send the OTP to the contact details—your email or phone number—that were linked to your previous Smart-ID account. You can’t update this information during the biometric registration process, so if you no longer have access to that old email or phone number, you’ll need to register using a different method.
Other options include logging in through online banking (especially useful if you’re a foreigner without a local ID), visiting a bank or telecom provider in person, or using a chip-enabled ID and an NFC-compatible phone.
In some cases, you might need to contact Smart-ID’s support team to update or recover your account info. It’s also worth noting that there are two Smart-ID account types: Full Access and Basic. And the method you choose might affect what services you can access. To avoid issues with OTP delivery, especially while traveling, keep your contact information current and secure.
OTP Not Arriving? Here’s What’s Going On
If your OTP password does not arrive within 60 seconds, don’t panic. It’s more common than you may think, and there are a few possible reasons.
First, know that OTPs are sent instantly, but sometimes delays may happen. One of the most common reasons is mobile network congestion or poor signal strength, which can slow down or block SMS delivery. If you’re traveling, roaming settings or unfamiliar local networks may interfere, so try to manually select a local network or switch to email verification.
Sometimes the delay isn’t on your end at all—system errors like server overloads on the provider’s side can prevent the code from being sent to you. To fix the issue, wait a moment and try resending the code. Make sure you’ve got a good signal, or switch to email verification if SMS isn’t working well. You can also try an authenticator app that works offline. As a last resort, reach out to support, for example, to help troubleshoot and get things moving.
To avoid these problems in the future, make sure your contact details are up to date, use the most reliable delivery method for your location, and check that your phone is set up to receive international texts if you’re abroad.
When OTPs Can’t Protect You?
One-time passwords are widely used to add an extra layer of security when logging into accounts or confirming transactions. However, they’re not completely safe and can still be exploited in several ways.
One common threat is phishing, where attackers send fake emails or messages pretending to be from legitimate companies to trick people into giving away their OTPs. Once they have the code, they can access personal accounts. Another serious risk is SIM swapping—this happens when a hacker convinces a mobile provider to switch your phone number to their SIM card, letting them receive your OTPs and break into your accounts.
Man-in-the-middle (MitM) attacks occur when hackers intercept OTPs during their journey from the sender to your phone by exploiting weaknesses in mobile networks. Also, if your contact information, such as your email or phone number, is leaked in a data breach, attackers can use that to reset passwords or steal OTPs.
SMS-based OTPs specifically have flaws. For example, messages can be delayed, intercepted, or sent to the wrong person if your SIM is compromised. To better protect yourself, it’s safer to use app-based OTPs or hardware security keys instead of SMS. You should also keep your email and phone number secure, be cautious of phishing attempts, and routinely check your accounts for suspicious activity.
The bottom line: here are the main ways OTPs can be hacked
- Phishing
- SIM Swapping
- Man-in-the-Middle Attacks (MitM)
- Leaked Contact Info
While OTPs are helpful, understanding their limitations and using stronger, layered security measures is key to keeping your data safe.
OTPs in Pop Culture: Not Just About Security!
Did you know that “OTP” is an abbreviation with several meanings, and it’s not just limited to tech?
In fandom culture, “OTP” stands for “One True Pairing,” which refers to a fan’s favorite romantic couple from a book, movie, or TV show—whether officially together or imagined by fans. This term has evolved since the late '90s, spreading through platforms like Tumblr and TikTok, where fans celebrate their OTPs through fanfiction, memes, and videos.
Additionally, OTP can simply mean “On The Phone,” referring to being on a call, or “One-Time Offer,” a limited-time marketing deal.
Can we just say that whether it’s securing your account or securing your heart, OTPs always come with a one-time, unforgettable connection?
The Future of OTPs: What’s Next?
The future of One-Time Passwords (OTPs) is changing with new technology that improves security and makes things easier for users. More companies are moving from SMS-based OTPs to app-based ones, which are faster and safer. Biometric methods like fingerprint and facial recognition are also being used alongside OTPs for extra security.
Static passwords will soon be a thing of the past, as OTPs, biometrics, and multi-factor authentication (MFA) become the new standard. But even the most advanced verification tools have one thing in common: a stable internet connection to work—especially when you’re abroad.
If you’re traveling or working remotely, your traditional SIM might not cut it. Try Yoho Mobile eSIM —and don’t let spotty connections or SIM issues lock you out of your digital life.
✅ Instant data access in over 190 countries
✅ Fast setup—no physical SIM needed
✅ Keep using Smart-ID, authenticator apps, and secure logins without interruption
✅ No roaming charges, no surprises
Whether you’re verifying your identity, logging into important accounts, or just need fast, secure internet on the go, Yoho’s eSIM has you covered.
