Same Growth, Different Margins: MercadoLibre vs. Sea Limited

Two e-commerce growth stories, both accelerating near 50% revenue growth in the same quarter. Both building fintech ecosystems to capture their users beyond buying and selling. Both selling shares priced well above today's profits.

The difference lives in what happens after the revenue number.

MercadoLibre's Q2 2026 earnings delivered $10.2 billion in net revenue, up 50% year over year — a headline that would win any stand-alone quarter. The stock fell. What drove it down was the margin line: operating income of $683 million, an EBIT margin of 6.7%, down 550 basis points from the prior year. MercadoLibre is spending its way through competitive threats, credit expansion, and logistics buildout, and the cost is eating faster than the top line is growing.

Sea Limited's Q2 2026 earnings posted $7.8 billion in revenue, up 48%. Almost identical growth. But Sea's gross margin expanded to 45.6% for the third straight quarter, and adjusted EBITDA climbed to $917 million. The stock surged nearly 14% in the days after the report. Revenue growth alone did not explain the reaction. The reaction was that Sea is getting more profitable while growing just as fast.

Same sport. Different margins. That is the match.

The Scoreboard

Both companies started 2026 growing at roughly the same pace. By the second quarter, neither had slowed:

MercadoLibre — $10.2 billion quarterly revenue, +50% year over year. Market capitalization near $100 billion. Trailing P/E ratio around 53. Stock price roughly $1,966, down nearly 19% from its 52-week high of $2,548.

Sea Limited — $7.8 billion quarterly revenue, +48% year over year. Market capitalization around $67 billion. Trailing P/E ratio approximately 43. Stock price near $123, having rallied sharply from a post-earnings pop of nearly 14%.

MercadoLibre generates roughly 40% more quarterly revenue but trades at a valuation roughly 50% higher. The gap has nothing to do with a revenue growth advantage and everything to do with whether investors believe the margin story.

Where the Margins Split

MercadoLibre's margin compression is not a single event. It is three simultaneous cost pressures.

The acquiring business in Mexico lost margin to higher device costs and one-time inventory restocking. Logistics absorbed elevated energy costs rather than passing them through. And the credit portfolio — now $16.4 billion, up 75% — carries deteriorating asset quality, with 90-day non-performing loans rising in a way management calls portfolio mix rather than fundamental deterioration. That distinction matters less if the provisions keep climbing.

Then there is the competitive front. Shopee, Sea's e-commerce platform, has entered Brazil and is outpacing broader market growth there. TikTok Shop is also in the marketplace. MercadoLibre responded by lowering free-shipping thresholds, cutting seller fees, and increasing marketing spend. That is what 550 basis points of margin erosion looks like in practice: it is the cost of defending a duopoly that no longer exists.

Sea is running the opposite playbook — not defending, but monetizing. Shopee's core marketplace revenue grew 65.6% in Q2, more than twice the 28% growth in gross merchandise value. The take rate jumped from about 8.5% a year ago to 14.6%. Advertising revenue grew more than 70% year over year, driven by AI tools that improved purchase conversion by 14% and cut service costs by 30% through chatbots handling 80% of customer queries. Shopee is not just selling more. It is earning more from every dollar of sales volume, and doing it by making sellers' advertising work better, not by cutting the fees it charges them.

Shopee's adjusted EBITDA for the quarter was approximately $255 million. That is thin — management's stated medium-term target is a 2% to 3% EBITDA margin on the e-commerce business. But Shopee does not carry Sea's profitability alone. Garena, the gaming division, generated $747 million in revenue and $430 million in adjusted EBITDA — a 56% margin. It is the cash engine that funds Shopee's expansion and makes the whole operation credible at scale.

MercadoLibre has no equivalent. Its three businesses — marketplace, payments, logistics — all draw capital. None of them produces the kind of standalone profit pool that absorbs losses elsewhere.

Credit: The Hidden Score

The fintech businesses look like mirror images on top-line growth — MercadoLibre's credit portfolio up 75%, Sea's loan book up 62% — but the quality metrics tell different stories.

MercadoLibre's total non-performing loan rate sits at 7.0% (15-90 days), with 90-day NPLs showing "meaningful deterioration." Management pointed to faster issuance and portfolio mix, not fundamental credit weakness. But faster issuance is exactly the condition where NPLs lag reality, and the provisions are a leading indicator regardless of the label.

Sea's Monee fintech division keeps its 90-day NPL ratio at 1.0%, stable quarter over quarter, even while adding 5.3 million first-time borrowers. The credit-loss provision jumped 71.5% year over year to $555 million, which is faster than revenue growth and worth watching. But a 1% NPL ratio at $11.1 billion in loans is a different quality profile than 7% at $16.4 billion, and the market has priced that difference into the spread between these two stocks.

Valuation as a Reflection of Confidence, Not Just Growth

MercadoLibre trades at roughly 53 times trailing earnings and 49 times forward earnings. Sea trades at roughly 43 times trailing earnings. Neither is cheap by absolute standards. But the gap matters because the revenue growth is nearly identical and Sea's growth quality — the margin expansion, the take-rate improvement, the diversified profit engine — is stronger in the current quarter.

The P/S ratio for MercadoLibre is approximately 2.8 times. Sea, with $31.2 billion in annualized revenue run rate, carries a P/S near 2.1. The valuation differential between two companies growing at the same pace, where one is compressing margins and the other is expanding them, represents the market's judgment that Sea's growth is more durable per dollar of invested capital.

That judgment could be wrong. MercadoLibre's AI investments — $80 million in the quarter alone — are already driving 73% year-over-year growth in advertising revenue. If those investments pay off faster than the competitive costs, the margin story reverses. The CEO has signaled that sequential margin stability in the second half of the year should come from improved Brazilian credit profitability offsetting commerce and acquiring investments. That is a conditional promise, not a guarantee.

The Design Lesson

This comparison works because both companies are asking the same question: can a regional e-commerce platform build a fintech moat wide enough to sustain growth without destroying margins? MercadoLibre answered with scale and aggression. Sea answered with monetization efficiency and a gaming-funded safety net.

The scoreboard at the current checkpoint favors Sea. The margin trajectory, the credit quality, the diversified profit structure, and the lower valuation multiple all point in one direction. MercadoLibre's counterargument is that Latin American penetration is deeper, the logistics network is more developed, and the AI investments are still in their earliest phase.

The variable that could reverse the score is credit. If MercadoLibre's portfolio quality holds and the margin recovery materializes in Q3, the 550-basis-point compression becomes a one-quarter story. If Sea's provisions keep accelerating faster than revenue while the NPL stays at 1%, the quality advantage may not be as wide as it appears.

Next checkpoint: MercadoLibre's Q3 earnings in November, and Sea's Q3 report shortly after. The score changes only if one of those margin narratives breaks.