Thirty years ago, if someone said something went viral, it would always strike fear. Today, “viral” is associated with most marketing goals of creating an internal growth engine for business. But the premise is still the same.

Contrary to popular belief, going viral isn’t all just luck. It’s something you can plan for, build, and integrate into your current workflow. If you look at well-known brands like Airbnb, Uber, and Dropbox, which all benefited from viral growth, you’ll notice their onboarding process and referral program helped drive their virality, and led to exponential growth.

The growth engine they used is known as a viral loop. Today, we’ll cover what a viral loop is and the best practices for building one.

What is a viral loop?

A viral loop is a mechanism that drives continuous referrals for sustainable growth.

It’s how you drive your existing customers to refer others to your brand, and in turn, get those new customers to tell even more people about you. This creates a lasting loop which can potentially lead to exponential viral growth.

All referral programs have the goal of creating viral loops and often share the same benefits when executed properly. Even if your growth isn’t exponential, you’ve still created a viral loop if your referral program drives continuous sharing and customer acquisition.

Advantages of creating viral loops

The two main advantages of creating viral loops are they are cost-effective and they operate through trust.

Cost-effective: When your customers share your brand with others, that’s free advertising. When done right, the results are almost like magic. One user becomes two, then four, then eight – you get the point. All without spending a dime, aside from your initial investment.

Trusted: In a survey conducted by Nielsen, 92% of people trust the recommendations of others more than messaging directly from businesses. Viral loops focus on optimizing this process to make sharing as easy and accessible as possible. Essentially, turning new clients into trusted sales reps.

How do viral loops work?

Here are the steps involved in creating a viral loop:

1. You gain a new customer. In the loop pictured below, this is the “purchase” stage.

2. You advertise the referral program to the customer, inviting them to share your product with friends. You offer the customer a valuable incentive in return for sharing with someone who eventually becomes a customer. This is the “desire to share” stage, where the customer is attracted by the referral program.

3. The customer thinks the incentive is valuable and refers you to their friends. This is known as the “share” stage.

4. The friends see and trust the message from your customer, which is the “see” stage. They become your new customer through the “purchase” stage.

5. These new customers also take advantage of the referral program, and it’s their turn to enter the “desire to share” and “share” stages. And the cycle continues.

the viral loop

How to create a viral loop: Best practices

When building your viral loop, its best to make sure you have a well-thought out funnel and referral marketing framework in place before you start running and optimizing your campaign. Here are our best practices, based on helping thousands of companies run referral programs:

Make sure you’re referable

Before you even start a referral program, you’ll need a referable product or service. This is your “core” of the viral loop!

Give customers a reason to share by delivering something remarkable, something that stands out from the rest of your market. This could be an unmatched product, stellar customer service, outstanding value, or a unique stance or story.

Once that’s sorted, you’re ready to crank up that word-of-mouth marketing by creating a viral loop.

Choose valuable incentives

Yes, your awesome product or stellar customer experience is crucial in why people want to share with friends. But they still usually won’t share unless there’s something valuable in it for them – a compelling referral reward. So, make sure the incentive is valuable for your customers, and reflects how much a new customer is worth to your brand. But think about your bottom line, too – the reward should also be cost-effective for your company to pay out consistently.

Rewards should be cumulative, meaning a user can keep earning rewards each time they successfully refer a friend. That way, people are incentivized to keep participating in the viral loop. You might also consider tiered rewards, which increase in value as someone makes more referrals.

Reward both parties

Use dual-sided rewards for referrer and friend, to both entice current users to refer and their friends to join.

Even with a valuable reward available to them, customers might not share because they’re afraid to “sell out” their friends for an incentive. But if their friends can get a reward as well, referrers will appreciate the chance to help their peers out.

A dual-sided reward also helps “close the loop,” as it gives referred friends a reason to purchase and keep the cycle going. Then, these friends can get another reward for referring friends of their own.

Figure out your loop’s entry points

Where and when will users be invited to refer? For example, will users be invited to refer right after they make a purchase? And how will you invite them into the viral loop? Promoting your program is key.

We recommend inviting customers to share on your thank you page (purchase confirmation page), or in an email sent shortly after a purchase. Or, if you’re a SaaS business, you might wait until customers reach an “aha moment” of realizing the product’s value, such as after they complete an onboarding or after they give positive feedback in-app.

Other than that, you should promote your program in regular emails, sent at least monthly to quarterly. Don’t stop at just emails dedicated to the program. You can also drop a sentence or two about the program in other emails you send, like newsletters.

Remove the friction

Once people have found the program, make sure it’s easy for customers to use it and share. Let customers access the program’s landing page with a unique One Click Access link, so they don’t need to register or set a password. Include this link in all referral program promotional emails.

And once they’re on the landing page:

  • Explain the program in as few steps as possible (we recommend using 3-4 bulleted steps).
  • Provide multiple sharing options, including email, social media, and a click-to-copy referral link.
  • Put the rewards and other benefits in a prominent spot, so customers know what’s in it for them.
  • Include a visible share button above the fold – customers shouldn’t have to scroll to find it.

Foster continued engagement

It’s also important to keep your registered program members engaged, so they continue to share and bring others into the viral loop.

We recommend sending monthly emails to all of your members, to remind them of the program and encourage further sharing.

You might also send emails right after customers receive a referral reward. If your program’s tiered, make things even more enticing and tell them how many referrals they need for the next highest reward.

Don’t forget the friend’s experience

People sharing is only half of the viral loop – referrals need to become aware of your brand and convinced of its value, so they purchase and start the loop with others.

Key to this is the message the referred friend receives through your program, as that’s often their first impression of your brand.  Here’s how to optimize this message for highest conversion rates:

  • Address the referral by name, and include the referrer’s name in the message as well.
  • Write the whole message from the peer’s perspective, not your brand’s.
  • Display the rewards on offer, and mention that they’re coming from a peer.
  • Explain the most important reasons why your brand is awesome, but concisely, in a conversational way, and from the referrer’s perspective.
  • Include an eye-catching CTA above the fold, that the friend will click to make a purchase

Keep optimizing your loop

For the best results, you shouldn’t just start your referral program and leave it be. Rather, check your program’s performance and keep tweaking it to deliver the best results.

If you’re not sure where to start or what KPIs to analyze in your testing, I recommend taking a look at your referral program’s leading indicators:

  • Aware: Do people know your referral program exists?
  • Shares: Are people telling others about your business?
  • Reach: Are the shares getting clicks and resonating?
  • Referrals: Are people converting after being referred?

Analyze and test each step of the viral loop to make your referral process is as effective as possible. Then, make changes.

  • For instance, if awareness seems low relative to your customer base numbers, improve your promotion.
  • If people know about your program but aren’t sharing, you might change up your reward.
  • If shares are high but reach and referrals are low, improve the message you send referrals. Also, add in a dual-sided reward if you don’t already have that.
Easily measure your growth with our free growth rate calculator!

How to analyze your viral loop

There are many things to consider when analyzing your viral loop.

  • Which channels do users come from? Which channels produce the most lasting users?
  • Should you enable users to refer through more channels (SMS, social media, in-app, etc. ?)
  • Would different referral program text, or positioning of the program, lead to more invites?
  • Might a different incentive be seen as more valuable by more people?
  • Which types of users are most likely to refer (for example, customers who have made more than one purchase, or customers who have renewed their subscription)?
  • Track key metrics:
    • What percentage of customers have successfully continued the loop (referred friends who become new customers)?
    • How long do referred customers stick around?
    • What’s your growth rate (in terms of new customers added)?

Follow other best practices for referral program design – here’s more on how to optimize your referral program.

Viral loop vs. viral marketing

A viral loop is similar to viral marketing. Both techniques aim to drive continuous sharing, but a viral loop is more customer-acquisition focused, while viral marketing has the goal of brand awareness.

The kind of viral loops we are focusing on in this article involve direct referrals, where customers personally refer friends to your business.

But sometimes, people use the term “viral loop” to refer to viral marketing. Viral marketing involves creating highly shareable content to drive brand awareness through social media sharing. Just like with the referral viral loop, the aim is to create a cycle of sharing – viewers share the content with friends, who, in turn, share with their friends.

While viral marketing is less predictable, anyone can create a viral loop if they follow the right methods.

viral loop vs viral marketing

Types of viral loop

Although all viral loops have the same structure, you need to decide on the type of viral loop you want to create – essentially, how you’ll motivate your users to refer. Here are some examples:

Savings: The referrer is motivated by a money-saving offer, like a discount or free product. A good example would be MeUndies, with their offer of a store credit for each successful referral.

Friendship/assistance: The referrer is motivated to share to help their friend. Uber can fall under this category, as well as value (the next category we’ll cover). With Uber, when you refer a friend, you both receive a free ride.

Value: The referrer is motivated because both they and their friend receive something from the referral. Snapchat’s viral loop runs with no incentives besides the value of using the social network with friends, proving that some viral loops are entirely free.

Charity: The referrer is motivated to share because the brand promises to donate to a charity for every referral. There are countless examples of this, but the most popular is the ALS Ice Bucket Challenge.

types of viral loops

Examples of effective viral loops

Let’s examine a few viral loop case studies, and what made each effective. You probably won’t become as viral as Dropbox, Uber, or Airbnb… but you can steal their secrets.

Dropbox

Dropbox is a cloud-based file sharing service and, by far, the most covered referral program of all time. There’s a good reason for this. Their referral program drove viral growth, generating close to 3 million new users within the first 30 days of launching their referral program.

What made their program so effective was its simplicity and ease of sharing. At the time, Dropbox was one of the first companies to provide advocates with a way to share directly with their Gmail contacts – making sharing way more accessible than ever before.

Dropbox utilized a dual-sided referral program – when you share your link with a friend and they register, you both receive 500MB of free storage space. The whole process was a very gratifying experience for all parties involved. Furthermore, to increase their chances of maximizing each advocate reach, the company created a points system where users could earn up to 1GB of free space.

Takeaways for your business:

  • If possible, design a two-sided incentive structure where both parties benefit.
  • Make sharing frictionless by providing multiple ways to share to a customer’s existing network.
  • Give users a way to keep track of their progress and referral status.

Uber

When Uber launched in 2009, many people thought to hop in a stranger’s car and have them drive you around seemed crazy. Eleven years later, Uber is a household name and available in over 65 countries. While Uber’s real success was caused by disrupting the traditional taxi industry, the way it built trust and converted everyone to start ridesharing was through referral programs.

Because Uber is the middleman, connecting crowdsourced drivers and everyday riders, it had to build two separate referral programs to drive demand for each. But for the sake of this example, we will only be focusing on the rider’s program.

For riders, the referral program is pretty straightforward. A new user signs up for Uber. They receive a free credit to enjoy their first ride. After their first ride is complete, they receive a notification to share Uber with their network using a personalized link. When a referral signs up using your link, you and your friend will each enjoy free credit towards your next ride.

Takeaways for your business:

  • Make your onboarding process frictionless, especially for referrals.
  • Ask for referrals when users hit a high point and are excited about your product or service. Uber did a great job of this by offering their promotion as soon as a user finished their ride.
  • Streamline your referral process. Keep in mind, you always want to make your referral program easy to understand and with as few steps as possible.

Airbnb

Airbnb is a travel platform that connects hosts who want to list their space to travelers looking for a place to stay. Similar to Uber, Airbnb had to change the mind of millions when it came to hospitality. To do this, Airbnb buckled down on growing a community through trust and goodwill. Focusing on this foundation of trust, they began their process of creating a referral viral loop.

Airbnb’s first attempt at a dual-sided referral program wasn’t a huge success. But after reviewing the hard data, its marketers saw that the program had a positive impact and could be leveraged more effectively.

Airbnb famously A/B tested different call-to-actions (CTAs) to see if people reacted differently to receiving $25 themselves or giving $25 to a friend. Thanks to this testing, the company found that the “giving” message was more effective, and was able to carry that data forward.

Throughout the referral program design process, Airbnb kept the focus on hard data, collecting it at every step of the viral loop and using it to inform decisions.

Airbnb would gauge the effectiveness of its campaigns through such KPIs as:

  • Conversion rate of new users
  • Conversion rate of new hosts
  • Number of referrals per customer
  • Conversion rate of new guests
  • Monthly active users sending invites
  • Potential revenue impact
  • Referrals by medium (email, social media, etc.)

Ultimately, the viral loop Airbnb would create through  the repeated testing would sharply increase the number of guests staying at its properties, from 21,000 in 2009 to over 500 million today.

The success of Airbnb’s early A/B referral test also led to a data-centric culture at the company. It allowed the company to bring on an in-house team of mobile engineers, data analysts, and designers to better optimize its entire customer experience.

Takeaways for your business:

  • Identify your key metrics for referral success and where you can improve your funnel. To get an in-depth look at this process, check out how pirate metrics are used in viral loops.
  • Compare different incentives, structures, and messaging using A/B testing.
  • Don’t be afraid to invest in research and development once you identify an opportunity for growth.

Create your own viral loop

Now that you know the fundamentals of viral loops, it’s time to create one for your business and drive referrals. Decide on your type of viral loop, and know the metrics you’ll use to track its success. For more on driving customer referrals, be sure to check out our eight step referral framework.