Why You Should Use Two-Factor Authorization for Transactions

Login and password have not been saved for a long time: phishing, database leaks and malware regularly steal credentials. Two-factor authorization (2FA) adds a second verification step - code or confirmation on an independent device. Even if the password is stolen, the attacker has nothing to confirm the operation. In financial services, online casinos and on exchanges, 2FA is the best "shield" against unauthorized write-offs and thefts.

How 2FA protects money

From phishing: the password was entered on a fake site - a hacker without the second factor will not enter and will not confirm the conclusion.

From guessing passwords: even a "strong" password can leak; 2FA makes it virtually useless to an attacker.

Changing details: without 2FA it is more difficult to change email, phone, payment addresses/cards.

From "quiet" conclusions: most services require a second factor specifically for operations - output/translation will not work.

2FA Views - What to Choose

1. SMS codes

Convenient, without applications.

− Vulnerable to SIM interception/duplicate, delays, roaming.

Where it fits: the base minimum when there are no other options.

2. TOTP applications (time codes 30 seconds) - Google Authenticator, Authy, 1Password, Microsoft Authenticator, etc.

Offline codes, independent of the telecom operator; high reliability.

− You need to carefully store backup/seed codes.

Optimum for most users.

3. App Push Confirmations

One click, fewer errors.

− Risk of "fluff fatigue" (automatic confirmation out of habit).

Good paired with device biometrics.

4. Hardware keys (FIDO2/U2F: YubiKey and analogues)

Maximum protection, resistance to phishing; works without code.

− Cost, you need to have with you; it is important to set up a spare key.

Choice for increased risks and large amounts.

💡 Priority scheme: Hardware key ≥ TOTP> Push> SMS.

Correct setting (so that it is both safe and without "pain")

1. Turn on 2FA in two places at once:

on account (login/critical changes), on transactions (withdrawal, change of payment details).

2. Make a reserve:

save backup codes to offline storage (password manager/sealed sheet);
for TOTP - save seed/QR or connect a second phone/profile;
for FIDO keys - enter two keys (main + spare).
3. Include white lists of addresses/cards (whitelist): output - only to pre-confirmed details.
4. Deny login without 2FA: If the service allows, require 2FA with each new device/browser.
5. Link 2FA to device biometrics: fingerprint/Face ID for in-app confirmations.
6. Security Notifications: Enable alerts for logins, password change/2FA, output attempts.

Anti-phishing and "hygiene" in 2FA

Never share codes with support staff - there's no real need.

Check the domain before entering the code; phishing sites often ask for 2FA "for a view."

Disable SMS forwarding from the operator; connect SIM replacement prohibition without personal visit/passport.

Install a lock screen on your smartphone and encryption - losing your phone should not give an attacker access.

For TOTP, use backup: transfer to a new phone is the most common access loss point.

Common mistakes and how to avoid them

Mistake	What threatens	How to
Left only SMS	SIM swap/intercept	Go to TOTP or FIDO2, leave SMS as reserve
No backup codes	Phone loss = lock	Immediately download/print backup codes, store offline
One hardware key	Loss/failure = long-term recovery	Configure two keys + alternative TOTP
Confirm push "on machine"	Confirmation of someone else's operation	Check amount/method/location on the screen, enable biometrics
No whitelists	Output to "left" address/card	Include trusted identity lists and change delay

Features for cryptocurrencies and casinos/financial services

Crypto: enable 2FA for login, output, adding addresses, API keys; use address-whitelist and cooldown.

Online casinos/bookmakers: 2FA + confirmation of withdrawal speeds up checks and reduces the likelihood of manual holds.

Banks/wallets: push/biometry or 3DS2 are preferred; to log in to the web room - TMS/key.

What to do if you lose the second factor

1. Use backup codes or a spare key.

2. If not, go through KYC recovery: keep up-to-date documents in advance.

3. After recovery, change the password, recreate 2FA, check whitelist and active sessions.

2FA Inclusion Mini Checklist (1 minute)

Add TOTP or FIDO2 (better both).
Save backup codes offline.
Enable 2FA for output/translations and change of details.
Enable I/O notifications.
Activate the whitelist of addresses/cards and the delay in changing them.

FAQ (short)

Is only 2FA enough for entry?

No, it isn't. Be sure to protect transactions (output/transfers) and changes in details.

Which is more reliable - SMS or application?

TOTP application or hardware key. SMS - basic reserve.

Is a hardware key required?

Not required, but gives a better level of protection. For large amounts - very recommended.

2FA is a simple action with a huge effect: it adds independent verification and "cuts" the main vectors of attacks on money and account. Set up TOTP or FIDO2, save backup codes, enable 2FA on critical operations and use whitelists - this way you eliminate 90% of the real risks in transactions.