AT A GLANCE

Notion
Sierra
2013
Founded
2023
San Francisco, California
HQ
San Francisco, USA
$343 Million
Total Raised
About $1.6 billion
Ivan Zhao
Founder
Bret Taylor and Clay Bavor
Collaboration
Type
AI
Private ($10B valuation)
Status
Private — $15.8B valuation (May 2026)

FUNDING HISTORY

Notion

Series B2020
$50M raised$2.0B val.
Series C2021
$275M raised$10.0B val.

Sierra

Seed2024
$110M raised$1.0B val.
Series A2024
$175M raised$4.5B val.
Series B2025
$350M raised$10.0B val.
Venture Round2026
$950M raised$15.8B val.

BUSINESS MODEL

Notion

Notion uses freemium pricing. The free plan is generous — unlimited pages and blocks for individuals.

The Plus plan is $10/user/month for small teams. Business is $18/user/month.

Enterprise is custom-priced. The free tier is intentionally powerful enough that individuals and small teams can use it forever without paying.

The revenue comes when those individuals bring Notion to their companies and entire organizations adopt it.

Notion also has an AI add-on at $10/member/month that adds AI writing assistance, summarization, and Q&A across your workspace.

Sierra

Companies pay Sierra to run their customer service with AI agents instead of hiring rooms full of humans. The agent talks to your customers over chat.

It answers questions. It processes returns.

It updates subscriptions. Here is the clever part.

Sierra charges based on outcomes, not seats. Brands pay when the AI actually resolves a problem, not just for having the software installed.

That pricing is unusual. Most software charges a flat monthly fee no matter what.

Sierra only gets paid when the bot does the job.

HOW THEY STARTED

Notion

Ivan Zhao studied cognitive science at the University of British Columbia, obsessed with the idea that computers should be creative tools, not just consumption devices. He was inspired by pioneers like Alan Kay and Douglas Engelbart who envisioned computers as tools for thought.

In 2013, he started Notion with the idea of building a tool that combined documents, databases, and project management into one flexible workspace.

The first version of Notion launched in 2015 and basically nobody cared. The product was too abstract.

People didn't understand what it was or why they needed it. The company burned through its initial funding.

By 2015, Notion was nearly dead — Zhao had to lay off almost the entire team.

With the last of his money, Zhao kept just one engineer — Simon Last — and moved to Kyoto, Japan, where the cost of living was a fraction of San Francisco. For over a year, Zhao and Last rebuilt Notion from scratch in a tiny apartment.

They rewrote the entire product, making it simpler and more intuitive. The 2.0 version launched in March 2018.

This time, it clicked. Product Hunt loved it.

Twitter loved it. Within months, Notion was growing 50% month over month.

Sierra

Bret Taylor had already done the impossible twice. He co-created Google Maps.

He later became co-CEO of Salesforce, chaired Twitter's board during the messy Elon Musk takeover, and became chairman of OpenAI in late 2023. Clay Bavor spent 18 years at Google, most recently running its Labs group.

The two friends left their big jobs in 2023 to build something together. They picked customer service on purpose.

It is the least glamorous corner of software. Their logic was simple.

Companies hate their support costs. Customers hate waiting on hold.

AI that actually resolves problems could fix both sides at once. They launched Sierra in February 2024 with $110 million from Sequoia and Benchmark.

HOW THEY GREW

Notion

Notion grew almost entirely through organic love. The product was so flexible that users built incredible things with it and shared them on Twitter, YouTube, and Reddit.

Template creators built entire businesses around selling Notion templates. YouTubers made "my Notion setup" videos that got millions of views.

Notion didn't need a marketing team because its users were the marketing team.

The template ecosystem was a massive growth driver. Notion made it easy to duplicate and share templates.

Productivity influencers and creators built elaborate systems — life dashboards, second brains, CRM systems, content calendars — and shared them with their audiences. Every shared template was a free advertisement for Notion.

The community strategy was deliberate. Notion hired community managers early and empowered super-users to become Notion ambassadors.

There are Notion meetups in cities worldwide. Notion Campus Leaders run groups at universities.

The company understood that for a tool this flexible, community was the best way to teach people what's possible.

Sierra

Sierra went straight for big brands, not tiny startups. SoFi, Ramp, ADT, Sonos and Brex signed up early.

By 2026 it said more than 40% of the Fortune 50 were customers. The trick was trust.

Enterprises are terrified of an AI bot going rogue and insulting a customer. So Sierra built guardrails and let each company control exactly how the agent behaves.

Bret Taylor's contacts did the rest. When the chairman of OpenAI calls a Fortune 500 CEO, they pick up.

Sierra hit $100 million in annual recurring revenue in November 2025, seven quarters after launch, and $150 million by February 2026. In April 2026 it launched Ghostwriter, which builds and deploys a new agent from a plain-English description.

THE HARD PART

Notion

The "too flexible" problem. Notion can do almost anything, which means new users often stare at a blank page and have no idea where to start.

The learning curve isn't steep, but it's wide. People give up before discovering the product's power.

Every Notion user remembers the moment it finally "clicked" — but many potential users never reach that moment.

Enterprise adoption has been slower than expected. Notion is beloved by startups and small teams, but large enterprises need things like advanced permissions, audit logs, compliance certifications, and admin controls.

Building enterprise features while keeping the product simple for individuals is a constant tension. Companies like Confluence (Atlassian) have decades-long enterprise relationships that are hard to displace.

Performance at scale has been a persistent complaint. Notion pages with hundreds of blocks or large databases can become sluggish.

The app has improved significantly but power users with massive workspaces still hit performance walls. For a tool that promises to replace multiple apps, it needs to be as fast as each individual app it replaces.

Sierra

Everyone is building AI customer service agents right now. Decagon has raised at a multi-billion valuation.

Salesforce, ServiceNow and Intercom all shipped their own agents. Sierra is not the cheap option.

It sells premium AI to giant companies that move slowly. The bigger risk sits underneath the product.

Sierra does not make its own AI models. It rents them from providers like OpenAI and Anthropic.

If those model makers decide to compete directly, Sierra's edge gets thin fast, and its co-founder chairing one of them only makes that question louder. A $15.8 billion valuation on roughly $150 million in revenue leaves almost no room for a stumble.

THE PRODUCTS

Notion

Notion is a workspace that combines notes, docs, wikis, project management, and databases into one tool. Pages can contain any mix of text, tables, kanban boards, calendars, galleries, and embedded content.

Notion Databases are the power feature — structured data that can be viewed as tables, boards, timelines, or calendars. Templates let users start with pre-built setups for everything from CRM to habit tracking.

Notion AI adds writing assistance, summarization, and the ability to ask questions about your workspace content. Notion Sites turns any Notion page into a published website.

Sierra

The core product is the Sierra AI agent. It is a branded customer service bot that companies deploy on their website, app, and phone lines.

It handles the boring stuff. Order tracking.

Refunds. Password resets.

Account changes. Sierra also built its own tools to test and monitor these agents so they do not make things up.

In 2024 the company added a voice version that talks to customers on the phone. In April 2026 it added Ghostwriter, a tool that builds and deploys a new agent from a plain-English description.

The whole pitch is one AI agent that carries your brand's name and never sleeps.

WHO BACKED THEM

Notion

Index Ventures, Sequoia Capital, Coatue Management, Dragoneer Investment Group

Sierra

Sequoia Capital and Benchmark wrote the first checks at launch in February 2024, $110 million between them. Greenoaks Capital then led both the $175 million round in 2024 and the $350 million round in September 2025.

In May 2026 Tiger Global and Google's GV led a $950 million round at a $15.8 billion valuation, with Benchmark, Sequoia and Greenoaks back in. That takes total funding to about $1.6 billion.

That is partly the product and partly Bret Taylor. Investors bet on founders who have already built billion-dollar things.

MORE COMPARISONS