Headline A/B Test: A Prosper Case Study

Hello from the content corner of growth design! 🤓

I’m Lily, a Staff UX Strategist & Content Designer working on growth at Prosper, a US-based consumer lending marketplace.

In this month’s newsletter, I’ll share a simple headline test that led to a +3.6% conversion rate on an upsell that led to $200k monthly incremental loan amounts.

Respectfully yours, on behalf of Word Nerds of the world,

Lily Binns

Understand a user need, identify a growth opportunity

Last year, Prosper’s Personal Loan design team devised a solution that turned a sour experience sweet and yielded an even sweeter business result.

Through qualitative research, we learned many borrowers weren't understanding the company would deduct an origination fee from their loan. Customers were often surprised and angered when they realized too late that they weren't receiving the full funds they needed.

💡 We designed to increase transparency and understanding and upsell the product by introducing an additional offer page in the loan application.

Social proof through the roof

I used social proof in a new offer page headline to let borrowers know they'd be in good company if they made another choice: "Many customers choose to increase their loan to cover the origination fee".

We show them how much cash they'd receive if they choose their current offer versus how much they'd receive if they select the "Popular option" in which the origination fee is added on top of their original loan request amount.

The net incremental lift for this growth initiative has been an estimated $6-8M in personal loan originations per month across all channels combined.

 Plus, we've seen positive customers reviews about the helpful transparency of the different options they'd been shown.

A light lift optimization test

Part 2️⃣: After this initial success, I was curious about optimizing the upsell page. I knew social proof had been effective, but I was concerned some users might experience anxiety when they saw the words in bold in the headline: "Many customers choose to increase their loan to cover the origination fee".

I put a headline test in the backlog and had a chance to run it in Q1. The 3 variants I wrote removed the words of concern and emphasized the benefit to the user. Guess which variant won!

Test Variants:

• A: More cash to you

• B: Do you want to cover the origination fee with your loan?

• C: Cash to cover the origination fee

The Winner: B! Do you want to cover the origination fee with your loan?

Why?

My hypothesis is that it won because it’s direct, clear, framed as a question, and isn’t sales-y.

And "cover the fee" seems like less scary language than "increase your loan".

🎂 This headline change alone gave us a +3.6% improvement in conversion rate for selecting the upsell to cover fees with the loan. This has resulted in ~$200K in incremental loan amounts per month. Some nice frosting on the cake.

Concluding thoughts

If you’re cooking up quick and easy test-and-learn ideas, my advice:

• ✅ Evaluate every piece of content in your flow and iterate variations of structure, truly user-centric value proposition content, and tone.

• ✅ Consider when and where users may feel anxiety, confusion, or ambivalence, and ask how you might do something to ease it with different language.

• ✅ Identify key decision-making moments for users where ye olde social proof could help make the business-benefiting decision for them easier.

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