AT A GLANCE

Block (Square)
Stripe
2009
Founded
2010
San Francisco, California
HQ
San Francisco, California (& Dublin, Ireland)
$590 Million
Total Raised
$8.7 Billion
Jack Dorsey
Founder
Patrick & John Collison
Fintech
Type
Fintech
Public (NYSE: XYZ)
Status
Private ($91B valuation)

FUNDING HISTORY

Block (Square)

Series A2009
$10M raised$40M val.
Series B2011
$28M raised$240M val.
Series C2012
$200M raised$3.3B val.
Series D2014
$150M raised$5.0B val.
IPO (NYSE: SQ)2015
$0 raised$2.9B val.

Stripe

Seed2011
$2M raised$20M val.
Series A2012
$18M raised$100M val.
Series B2014
$80M raised$1.8B val.
Series C2016
$150M raised$9.2B val.
Series D2018
$245M raised$20.0B val.
Series E2019
$250M raised$35.0B val.
Series H2021
$600M raised$95.0B val.
Series I (Employee Tender)2023
$6.5B raised$50.0B val.
Secondary Sale2025
$1.0B raised$91.5B val.

BUSINESS MODEL

Block (Square)

Block makes money across several business lines. Square (the seller ecosystem) charges merchants a flat percentage per transaction — 2.6% + $0.10 for in-person payments, higher for online.

Cash App takes a fee on instant deposits, Bitcoin trading, and Cash App Pay transactions. Afterpay (acquired for $29 billion in 2022) earns merchant fees on buy-now-pay-later transactions.

TIDAL is the music streaming service (acquired from Jay-Z). Block also earns Bitcoin revenue — Cash App is one of the largest Bitcoin brokers in the US, though margins on BTC trading are razor-thin.

Stripe

Stripe charges a flat 2.9% + $0.30 per transaction. That's it.

No setup fees, no monthly fees, no hidden charges. The simplicity is the product.

When a customer pays on a website using Stripe, Stripe handles everything — fraud detection, currency conversion, bank transfers, tax calculation, compliance. The merchant just sees money arrive in their account.

On top of the core payments, Stripe has built an entire financial infrastructure stack. Billing for subscriptions, Connect for marketplace payments, Atlas for incorporating a company, Issuing for creating virtual cards, Treasury for banking-as-a-service, and Radar for fraud prevention.

They're basically building the financial plumbing for the entire internet.

HOW THEY STARTED

Block (Square)

The origin story starts with Jim McKelvey, a glass blower in St. Louis and old friend of Jack Dorsey.

In 2009, McKelvey lost a $2,000 sale on a glass faucet because he couldn't accept credit cards. The customer wanted to pay with Amex.

McKelvey couldn't process it. The sale fell through.

McKelvey called Dorsey, who was already CEO of Twitter, and they started brainstorming. The problem was obvious: millions of small businesses, street vendors, farmers market sellers, and independent contractors couldn't accept credit cards because merchant accounts required monthly fees, credit checks, and clunky hardware that cost hundreds of dollars.

Dorsey and McKelvey wanted to make it so anyone could accept a credit card using just their phone.

They built a tiny white card reader that plugged into a smartphone's headphone jack. The reader cost almost nothing to manufacture and Square gave it away for free.

The software was simple — swipe the card, enter the amount, the customer signs on the screen, done. Square charged a flat 2.75% per transaction with no monthly fees, no contracts, and no minimums.

The product launched in 2010 and spread through small businesses like wildfire.

Stripe

Patrick Collison was 19. His brother John was 17.

They had already built and sold a company — Auctomatic, an eBay auction tool — for $5 million while still teenagers in Limerick, Ireland. Patrick went to MIT, John went to Harvard, and they both dropped out because they had a better idea.

The idea was embarrassingly obvious in hindsight. In 2010, accepting payments on the internet was a nightmare.

You had to get a merchant account, negotiate with a payment processor, deal with a gateway provider, handle PCI compliance, and write thousands of lines of code. It took weeks or months.

The Collisons thought it should take five minutes.

They built a simple API — seven lines of code — that let any developer start accepting credit card payments immediately. No merchant account.

No paperwork. No phone calls with banks.

Just paste seven lines of code and you're in business. They originally called it /dev/payments, then changed it to Stripe in 2011.

Peter Thiel and Elon Musk — the PayPal mafia — were among the first investors. Sequoia and Andreessen Horowitz piled in soon after.

The Collisons had built exactly what every developer on Earth had been wishing for.

HOW THEY GREW

Block (Square)

Square grew by giving away the hardware. The card reader was free.

That eliminated the biggest barrier for small businesses. A food truck operator, a yoga instructor, a farmers market vendor — anyone could start accepting cards in five minutes without spending a dollar upfront.

Square made its money on the transaction fees that followed.

The simplicity was the pitch. Traditional merchant services involved contracts, monthly minimums, tiered pricing, and hidden fees that required a finance degree to understand.

Square charged one flat rate for everything. No surprises.

That transparency built enormous trust with small business owners who had been burned by traditional processors.

Cash App grew through peer-to-peer payments and a brilliant viral strategy. The app launched in 2013 as a simple way to send money to friends.

Rappers, influencers, and content creators started using their $cashtag for tips and payments. Cash App sponsored hip-hop events and partnered with musicians.

By 2024, Cash App had over 55 million monthly active users — more than most banks.

Stripe

Stripe grew almost entirely through developer love. They didn't hire a sales team for years.

They didn't run ads. They just built the best developer documentation anyone had ever seen and let word of mouth do the rest.

The developer-first strategy was deliberate. The Collisons realized that in a startup, the developer usually decides which payment provider to use.

If you make the developer happy, you win the company. Stripe's API documentation became legendary — clear, beautiful, with working code examples in every language.

They also grew by growing with their customers. Early Stripe customers included tiny startups that later became giants — Lyft, DoorDash, Instacart, Shopify.

As those companies scaled to billions in revenue, Stripe's processing volume scaled with them. Stripe didn't need to acquire new customers because its existing ones kept getting bigger.

The international expansion was methodical. Instead of launching everywhere at once like Uber, Stripe carefully added country after country, making sure each one worked perfectly with local payment methods, currencies, and regulations.

By 2024 they were processing payments in 195 countries.

THE HARD PART

Block (Square)

The Afterpay acquisition for $29 billion in 2022 was controversial. Buy-now-pay-later was already facing regulatory scrutiny and growing delinquency rates.

Critics argued Dorsey overpaid at the peak of the market. Afterpay's revenue growth slowed significantly after the acquisition, and write-offs on bad consumer debt increased.

It remains the biggest bet Block has ever made.

The Bitcoin obsession worries investors. After renaming Square to Block in December 2021, Dorsey went all-in on Bitcoin — investing company cash in BTC, building Bitcoin mining hardware, and creating TBD (a Bitcoin-focused developer platform).

While Cash App's Bitcoin revenue is huge on paper ($10+ billion annually), the margins are tiny. Investors question whether the Bitcoin focus distracts from the core payments business.

Competition is intense on every front. Square competes with Stripe, Toast, and Clover for merchants.

Cash App competes with Venmo, Zelle, and Apple Pay for consumers. Afterpay competes with Klarna, Affirm, and bank-native BNPL products.

Block has to fight multiple wars simultaneously with finite resources.

Stripe

Valuation whiplash. In 2021, Stripe hit a peak valuation of $95 billion during the fintech boom.

By 2023, they had to mark it down to $50 billion during the tech correction — a 47% drop that made headlines everywhere. Employees who had been paper millionaires suddenly weren't.

The valuation has since recovered to $91 billion after a secondary share sale in 2025, but those two years were rough for morale.

Competition is relentless. Adyen, the Dutch payments company, has been eating into Stripe's enterprise market.

Square (now Block) competes on the small business side. PayPal is everywhere.

New fintech players pop up constantly. The payments business has razor-thin margins and everyone is fighting for the same 2.9%.

Going public is the elephant in the room. Stripe has been expected to IPO for years.

Investors, employees, and the media keep asking when. The Collisons have consistently said they're in no rush, but with $8.7 billion raised and thousands of employees holding stock options, the pressure to provide liquidity is enormous.

As of 2025, they've opted for secondary sales instead of a public offering.

THE PRODUCTS

Block (Square)

Square is the merchant ecosystem — point-of-sale hardware, payment processing, invoicing, payroll, loans, and online stores for businesses of all sizes. Cash App is the consumer side — peer-to-peer payments, direct deposit, investing, Bitcoin buying, and the Cash App Card (a debit card).

Afterpay is the buy-now-pay-later product — split any purchase into four interest-free payments. Square Banking offers business checking accounts and loans.

Square Online lets merchants build e-commerce websites. TIDAL is the music streaming platform that pays artists higher royalties.

Stripe

Stripe Payments is the core — accept credit cards, debit cards, Apple Pay, Google Pay, and 135+ payment methods in 195 countries. Stripe Connect lets marketplaces and platforms pay out to sellers (Shopify, Lyft, DoorDash all use it).

Stripe Billing handles subscription and recurring billing. Stripe Atlas lets you incorporate a US company from anywhere in the world — fill out a form, get a Delaware C-corp, bank account, and tax ID in days.

Stripe Radar uses machine learning to block fraud in real time. Stripe Treasury lets platforms offer banking services to their customers.

Stripe Tax automatically calculates and collects sales tax in every jurisdiction.

WHO BACKED THEM

Block (Square)

Khosla Ventures, Sequoia Capital, Kleiner Perkins, Visa, Goldman Sachs, GIC (Singapore)

Stripe

Peter Thiel, Elon Musk, Sequoia Capital, Andreessen Horowitz, General Catalyst, Founders Fund, Tiger Global, GV (Google Ventures), Goldman Sachs, Baillie Gifford

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