The YC growth playbook: from day one of the batch to a repeatable pipeline

Every accelerator founder gets the same advice. Talk to users, do things that don't scale, measure growth every week. The advice is right. What it does not give you is a map of how growth changes from the first week of the batch to the moment a Series A investor asks where your pipeline comes from.

This is that map. It splits the first two years into four stages, with the moves, the numbers and the mistakes at each one. It is the pillar of the YC growth playbook series, and every other article in the series goes deeper on one part of it. Start here, then follow the links into the stage you are in.

What is the growth playbook for YC startups?

The growth playbook for YC startups is a sequence of four stages: the batch, Demo Day, the first 100 customers and a repeatable pipeline before Series A. Each stage has one goal, one number that proves it and one mistake that founders make most often.

The stages matter because the right move changes. During the batch, manual effort beats any system. After Demo Day, the same manual effort becomes the bottleneck. Founders who stall usually keep running the playbook from the previous stage.

The money behind these stages is fixed and public. YC's standard deal is $500,000 in total: $125,000 on a post-money SAFE for 7% of the company, plus $375,000 on an uncapped SAFE with a most favoured nation provision. How you spend it on growth is covered in how to spend the YC $500K.

How do YC startups grow during the batch?

YC startups grow during the batch by choosing one growth number, setting a weekly target and recruiting every early user by hand. Paul Graham's benchmark is plain: a good growth rate during YC is 5 to 7% a week, 10% a week is exceptional, and 1% is a sign you have not yet figured out what you are doing.

Measure revenue if you charge. Graham calls revenue the best thing to measure and active users the next best for startups that are not charging yet. YC is a three month programme that now runs four times a year, so the weekly rate is your only honest signal inside such a short window.

The key moves in the batch

1. 1Write your growth number on one line and post it every Monday. Revenue first, active users if you are not charging.
2. 2Name the buyer. One title, one company size, one trigger that makes them look for you this quarter.
3. 3Recruit by hand. Graham's essay on doing things that don't scale is direct about it: you can't wait for users to come to you, you have to go out and get them.
4. 4Treat your first B2B customers as the whole company. Graham's advice is to keep tweaking until you fit their needs perfectly.
5. 5Keep a log of every conversation, objection and reply. It becomes your positioning and your first sales copy.

The mistake here is building a system too early. A batch founder who spends week three configuring sequencing tools has nothing to put in them. The full 12-week plan is in how to run your three months in an accelerator as a growth sprint.

What traction should you show at Demo Day?

Show the growth curve and the number behind it, first. YC's own guide to Demo Day pitches, written by Geoff Ralston, tells founders not to bury the lead and to open with impressive traction when they have it.

The room is full of investors and the time is short. Ralston calls it distressingly short whatever the slot. His guidance is that the goal is to intrigue listeners enough that they want to meet you and learn more. The pitch wins meetings. The meetings win the round.

• Your growth number and its weekly rate across the batch.
• Named design partners or paying customers, with what they pay.
• A concrete bottom-up market: what you can sell for and how many buyers exist.
• A one-line answer to where the next customers come from.

That last line is where most founders are weakest. "Our network" is the honest answer for most batches, and investors know it. The founders who stand out can already point to a second source of pipeline.

How do you get your first 100 customers after YC?

You get your first 100 customers by moving past your own network on purpose: an account list agreed before anything is sent, the founder as the voice in every channel, and each channel tested against that list for four to six weeks before it gets more budget.

The first ten customers usually come from people who already trust the founder. The next ninety do not know you. They look you up before they reply, so your profile, site and proof have to be ready for them. That is why repair comes before volume.

1. 1Close the seed round fast, then protect the founder's calendar for selling and building.
2. 2Agree a target account list with whoever closes deals. Every channel works against the same list.
3. 3Fix what buyers check: the founder's profile, the site, the case study, the sending domains, the CRM.
4. 4Turn the proof you already have into assets: one case study, one founder essay, one webinar topic.
5. 5Run controlled tests. One variable per test, judged on replies and calls booked.
6. 6Keep the founder in every room. They run the calls, the demos and the terms.

The mistake at this stage is the hire too early. A sales team needs a playbook to follow, and at this point there is no playbook to hand over and the message is still being found. The detail is in from 10 design partners to 100 customers and in how to win paying design partners.

How do you build a repeatable pipeline before Series A?

A repeatable pipeline is one that grows on a schedule you control: three or more channels producing qualified deals the founder did not originate, measured every month, with budget moved to what converted. That is the pipeline a Series A investor wants to see.

You have less time than the headlines suggest. Carta's analysis of more than 3,000 US startups, published in October 2025, found 15% raised their next round in less than a year, while 39% raised their Series A three or more years after the prior round. Carta's advice is to plan on making seed cash last 1,000 days, or 2.7 years.

A thousand days is enough to build a pipeline that works without the founder's whole calendar. It is not enough to rebuild one after a year of hiring the wrong function. The metrics investors check are in the pipeline numbers Series A investors want to see.

Who should own growth at a seed-stage B2B startup?

The founder should own the voice and the close, and one senior team should own everything around them. There are three ways to run go-to-market at this stage, and only one keeps both speed and the founder's voice.

• Hire a sales team. Too early. There is no playbook to hand over yet and the message is still being found.
• Leave it all to the founder. Too slow. Every hour spent prospecting is an hour away from the product.
• Amplify the founder. Speed. The founder's voice reaches more of the right people and their hours go into calls that close.

Amplifying the founder splits the work cleanly. The founder owns the product and roadmap, the thesis and the voice, every sales call, closing and terms. Codax amplifies with target lists and buying signals, copy written with the founder, LinkedIn and email outreach at volume and a monthly pipeline review. Copy is tested together every round, and what books calls gets more volume.

This is a growth department built for founder stage. A growth department is one senior team that owns qualified pipeline end to end, from strategy to execution, under a single accountable lead. The five phases run in the founder's terms: Assess the thesis and the buyer, Fix the profile and positioning, Build the lists and sequences, Test the copy on replies and calls, then Scale what works. The detail is on how we work, and the wider argument is in founder-led sales does not scale, the founder can.

What does the playbook look like in practice?

It looks like two accelerator-stage companies with very different buyers, both using the founder as the sender and a tested account list as the target. One sold software to ecommerce brands. The other sold to owners of businesses they had spent years building.

AI personalisation for ecommerce

An accelerator-stage martech startup building AI-driven 1:1 personalisation for ecommerce and DTC brands. It was pre-revenue with a working product, and the founder needed paying design partners to prove pricing and shape the roadmap while building and raising. Generic outbound was getting ignored.

Four moves changed it. A tight ICP of DTC brands in the $5M to 30M revenue range, plus a few larger groups as stretch accounts. Outreach from the founder's LinkedIn and email, in their words, sharpened every round. Copy angles on conversion, order value and repeat purchase, keeping what booked calls. A design partner waitlist that kept brands warm and created urgency.

The result was 17 brands in qualified pipeline worth $472K, 4 brands with an LOI signed, and 3 paying design partners worth $126K ARR at $3.5K a month each. The $15M to 30M revenue band held 8 of the 17 brands and 43% of pipeline value.

Revenue cycle AI

An accelerator-stage revenue cycle AI company that automates billing and collections and grows by partnering with and then acquiring independent RCM companies, running them on its own AI. The buyer is an owner deciding who to trust with their business, so standard SaaS outbound does not start the conversation.

Outreach went straight to founders and owners of independent billing and revenue cycle firms, never procurement. The message was about their future: succession, staffing, margins and the cost of keeping up with technology. A design partner offer lowered the stakes. The founder ran every conversation from first call to terms. The result was $8M ARR in design partnership across two acquisitions, from a $15M acquisition pipeline.

Later-stage engagements show the same pattern at larger scale. In the agentic AI healthcare engagement, $1.02M ARR closed in seven months from LinkedIn and email, channels that had produced none, and the CEO as the sender produced 3x the replies. Read the agentic AI healthcare case study.

What are the biggest growth mistakes from batch to Series A?

The biggest mistakes are running the last stage's playbook in the next stage, hiring before there is a playbook and scaling a channel before it has been tested. Each one costs months that a seed company does not have.

• Batch: building tooling before you have a buyer and a message.
• Demo Day: burying traction behind the story.
• First 100 customers: sending volume before the profile, site and proof are ready for buyers who look you up.
• Before Series A: a pipeline that still depends on the founder's network, with no second channel trending up.

Pick the stage you are in and start with its first move this week. If you want the system built around your voice while you keep every call, start with how we work or browse the full accelerator founders series.