Nubank, the digital bank that has become a favorite among growth-focused investors, reported a third-quarter profit of $1.09 billion and said artificial intelligence is helping it keep costs in check by slowing its hiring pace. The company also nudged up its full-year efficiency target, a sign that its push to grow without adding headcount is paying off.
The results, reported by Reuters, show revenue of $6.26 billion for July through September, roughly in line with what analysts had expected. Net income of $1.09 billion also matched forecasts. But the more notable development was the bank's updated outlook: it now expects its efficiency ratio to land between 19% and 19.5% for the full year, improved from its earlier target of about 20%.
What is an efficiency ratio?
For a bank, the efficiency ratio is a simple measure: it shows how much it costs to generate each dollar of revenue. A lower number is better, because it means the bank is keeping a larger slice of its revenue as profit. Nubank's target of 19%-19.5% is already low by industry standards, and the company says it can do even better than originally planned.
Chief Financial Officer Rob Livingston told Reuters that the biggest driver of the improvement was a slowdown in hiring. He attributed that mainly to AI tools that are boosting staff "capacity and productivity." In plain terms, the bank is finding that its employees can handle more work with the help of AI, so it doesn't need to add as many new people to support growth.
This is a theme that has been echoing across the tech and financial sectors. Companies are increasingly pointing to AI as a way to control costs while still expanding. For Nubank, which has grown rapidly since its founding in Brazil, the ability to scale without a proportional increase in headcount is a key part of its profitability story.
Credit quality: the risk check
While the cost picture looks better, the bank's loan book is showing some signs of strain. Nubank's credit portfolio grew 33% year over year, but the share of loans that are 90 days past due rose to 7.3% from 6.7% in the previous quarter. That is a meaningful jump, and investors will be watching to see whether it signals a broader deterioration in credit quality.
Management, however, is framing the increase as a seasonal blip and a result of an earlier push into higher-risk customers, rather than a sign of systemic trouble. They argue that the portfolio is still healthy and that the uptick is manageable.
For everyday investors, this is the classic tension in banking: growth often comes with more risk. Nubank is expanding its lending, and some of those new borrowers may be less creditworthy. The bank's ability to keep delinquencies from spiraling will be crucial to whether it can maintain its improved efficiency target.
What it means for investors
Nubank's efficiency target is more than just a number. Because the bank's cost base is relatively small, even a one-point move in the efficiency ratio can have a noticeable impact on profits. That is why the company's guidance matters: it tells investors that small shifts in costs can translate into larger swings in the bottom line.
Banks that can grow revenue without adding many people tend to show stronger "operating leverage" — meaning profits rise faster than sales because costs don't keep pace. Nubank is essentially telling the market that AI is helping it achieve that kind of leverage. This is a story that has resonated with investors in other AI-driven companies, and it could support Nubank's stock if the trend continues.
But the durability of that story depends on credit. If delinquencies keep climbing, the bank may have to set aside more money for loan losses, which would eat into the cost savings from slower hiring. The 19%-19.5% efficiency target assumes that loan losses stay within a certain range. If they don't, the target could be at risk.
Investors will likely keep a close eye on Nubank's monthly delinquency data and any commentary from management about credit trends. The bank's ability to balance growth, AI-driven efficiency, and credit quality will determine whether it can sustain its current momentum.
For those watching the broader market, Nubank's results also offer a glimpse into how AI is reshaping the financial industry. The company is not alone in using AI to cut costs — other banks and fintechs are doing the same. But Nubank's aggressive adoption of the technology, combined with its already low cost base, makes it a notable case study.
As always, past performance is not a guarantee of future results, and investing in individual stocks carries risk. But for investors who follow the banking sector, Nubank's latest quarter is a reminder that efficiency and growth can go hand in hand — if credit risks are managed carefully.
