Imagine this: your customer tries to log in, initiates an action, and waits patiently for their One-Time Password (OTP) to hit their inbox. Seconds pass… then a minute… and nothing arrives. For them, it’s a frustrating. ItsIt’s an inconvenience. For your business, it’s a lost session…possibly a lost customer.
As new security regulations continue to enforce 2FA (Two-Factor Authentication) and MFA (Multi-Factor Authentication), OTPs have quickly become the backbone of digital security. Particularly, for retail, finance, and insurance companies, they’re now a non-negotiable element of the customer journey.
But when an OTP doesn’t show up, the consequences run deeper than just a momentary delay.
The Hidden Cost of Email Delivery Failures
An undelivered OTP is more than a technical hiccup: it’s a direct hit to your entire communication ecosystem.
- Customer experience suffers: A user who can’t log in or complete a transaction instantly feels frustration and distrust.
- Brand reputation declines: Every bounce or undelivered message chips away at your reliability.
- Deliverability and performance takes a long-term hit: Repeated failures lower your sender score, reducing inbox placement rates and making future campaigns even harder to deliver.
And in fiercely competitive markets like retail and insurance, a little bit of friction can send customers straight to a competitor. There’s no room for uncertainty when trust is part of the product.
The Need for Reliable Transactional Email Delivery
OTPs, password resets, order confirmations, and authentication links all share one requirement: instant, guaranteed delivery. Customers expect a seamless, real-time experience. They don’t want to refresh a page. They don’t want to click “resend OTP.” And they certainly don’t want to contact support.
For businesses, latency or failed delivery is more than an inconvenience. It’s a critical risk. When security and trust are on the line, unreliable email infrastructure is not an option.
The Retarus Solution: Transactional Email (TEM)
Retarus TEM ensures every critical message – whether it’s an OTP, password reset, or urgent notification – reaches the inbox quickly and reliably.
Key Benefits
- Guaranteed inbox delivery: for high-volume transactional email
- Unlimited scalability: From 5,000 to more than 100,000 emails per hour – without throttling
- Peak performance under pressure: Consistent throughput during traffic spikes such as promotions or seasonal demand
- Complete transparency: Real-time dashboards and monitoring provide instant operational insights
- Data integration: Optional real-time export in a standardized format, ready for analysis
- IP Sanitization & Optimization: Traffic flows through whitelisted, CSA-certified IPs to maximize deliverability and sender reputation
With TEM, your emails don’t just get sent. They get delivered.
What Reliable Delivery Means in Practice
Here’s what robust transactional email performance translates to in the real world:
- Instant access: OTPs arrive immediately, allowing fast, frictionless authentication.
- Improved customer experience: Faster access = happier users = reduced drop-offs = increased revenue.
- Enhanced sender reputation: Reliable delivery today builds the foundation for long-term inbox success.
- Optimized infrastructure: Whitelisted IPs and strict sanitization ensure traffic consistently reaches the intended destination.
Real-World Impact
This level of reliability has already resonated strongly with leaders in insurance and retail – industries where speed, trust, and security simply cannot fail.
A standout example is a major, global French insurance company, who relied on Retarus TEM to ensure consistent OTP distribution and saw measurable improvements in customer experience and retention. Their success highlights a simple truth: when your authentication layer is dependable, everything else gets easier.
Don’t Risk Your Reputation on Unreliable OTP Delivery
In an era where 2FA and MFA are foundational to digital security, transactional email is no longer just a back-office utility. It’s business-critical infrastructure.
When every OTP counts, you can’t leave delivery to chance. With Retarus Transactional Email, you ensure your most important messages – especially authentication flows – always reach the inbox on time.
You’re not just sending messages. You’re delivering trust, reliability, and a superior customer experience.
Learn more about Retarus Transactional Email



