How do you onboard new clients? 6 stages + templates for 2026

How you onboard new clients plays a big role in retention. After reviewing onboarding processes across consulting firms, agencies, and freelance businesses, I've identified the steps that consistently reduce early churn. Here's what works in 2026.

What is client onboarding?

Client onboarding is the process of integrating a new client into your business after they sign a contract. You move them from prospect to active client by setting expectations, collecting information, and establishing how you'll work together.

The process covers contract signatures, payment setup, kickoff calls, and file sharing. Most service businesses finish onboarding in 1 to 2 weeks, though complex engagements may take longer. However, firms using tools like Assembly can significantly shorten their onboarding.

I've found that firms that skip structured onboarding often face problems months later. Clients feel confused about deliverables, payment timelines drag out, and small miscommunications can compound into bigger issues.

Why client onboarding matters

A structured onboarding process prevents common problems that show up weeks or months later. Here's what changes when you get it right from the start:

• Sets expectations before problems arise: Projects expand beyond their original scope when deliverables aren't documented during onboarding. Clear onboarding defines what's included, what's not, and how changes get handled before work begins. I recommend documenting the scope, deliverables, and timeline in writing rather than relying on verbal agreements.
• Reduces churn and increases retention: The first 90 days often determine whether a client stays or leaves. Poor onboarding creates friction that clients remember long after you've delivered the work. I've noticed that firms lose clients not because of bad work, but because the setup felt disorganized.
• Gets you paid faster: Clients who understand your billing process pay invoices on time. Onboarding is where you collect payment methods, explain invoice timing, and set expectations for how transactions work. When you skip this step, clients receive their first invoice without context. These small gaps create delays that compound across every billing cycle.
• Creates referral opportunities: Happy clients refer others, and onboarding is your first chance to create that positive impression. Referrals often come from clients who felt taken care of from day one. That experience sticks with them when someone asks for a recommendation.
• Saves you time on every future client: A repeatable onboarding process removes the need to rebuild your approach for each new client. What takes three hours for your first client drops to 30 minutes by your tenth because you've eliminated the guesswork. This efficiency scales as you grow without requiring more team members.

How do you onboard new clients with Assembly? 6 stages

Most service businesses treat onboarding as a simple checklist, but the reality is messier. The process starts during your sales calls and stretches through the first few months of delivery. Each stage builds trust, aligns expectations, and turns a signed contract into a working relationship.

Below is how the client onboarding process works using Assembly, a client portal platform built for service firms. Our software handles contracts, billing, intake forms, and ongoing communication in one place, which makes it useful for demonstrating how the onboarding stages connect. 

Here's how each onboarding stage works:

Stage 1: Pre-onboarding (before the contract is signed)

Pre-onboarding happens during the sales process, but the information you gather here determines how smoothly onboarding goes later. You're aligning on scope, pricing, and timeline while capturing the client's pain points and goals.

I recommend creating scalable onboarding processes for your clients during this stage. Here’s how two types of businesses could do it: 

• For a consulting engagement, this might mean creating an onboarding template for a business audit to understand clients’ current processes, bottlenecks, and decision-makers. 
• For a marketing agency, it's documenting or collecting brand guidelines, setting up approval workflows, and researching existing campaigns.

Start by creating the client record in your Assembly CRM as soon as the work is confirmed. Use internal notes, custom fields, or private chats to capture pricing decisions, edge cases, and scoping context that shouldn't be client-facing. This gives your team a shared starting point before the client is invited.

Stage 2: Contract and payment

The contract formalizes what you agreed to during pre-onboarding. This is where you lock in scope, deliverables, and pricing before any work begins.

Don't start work until both the contract is signed and the payment method is on file. I've seen too many firms skip this step and regret it later when scope disputes or payment delays surface.

Send the contract for electronic signature using Assembly's e-signature feature. Upload your PDF, add signature fields, and send it through the branded client portal or by email. You can track the status and get audit trails so you know exactly when it's signed.

Once the contract is signed, you can use the Billing App to create invoices, share payment links, and have clients enter payment methods. Keep the contract and billing info on the same client record you created earlier so the scope and payment terms are locked in before work begins.

Stage 3: Welcome and kickoff

Once the contract is signed, prepare the client portal before inviting the client. Use Assembly's Files App to set up folders for uploads like brand assets and legal documents. Then use our Messaging App to set up an automated welcome message that invites the client into their portal and outlines the next steps.

Have your clients schedule a kickoff call with you via Assembly’s Calendly integration to introduce your team, review the plan, and share how you'll work together. I suggest covering goals, deliverables, communication preferences, and the first milestone. This is where you turn the signed agreement into a working relationship.

This setup keeps contract signing and billing separate from the portal invitation, so you control the sequence and start the engagement on solid ground.

Stage 4: Information gathering

You can use Assembly's Forms App to create an intake form or questionnaire that collects the specific details you need to start work. Request access to tools, accounts, or assets that your team will use during the engagement.

A marketing agency might ask for brand guidelines, ad account access, and past campaign data. An accounting firm might request access to bookkeeping software and prior-year financials.

The Tasks App allows you to create tasks that reflect how onboarding actually happens for your team. Assign an owner to every task and add due dates for steps that tend to stall, like collecting access or confirming kickoff details.

Stage 5: Internal handoff

Brief your team on the client's background, goals, and scope. Assign an account manager or point of contact as a custom field in the CRM and set up the project in your task or workflow tool.

I've found that an internal meeting to review intake form responses and assign first tasks prevents miscommunication later. This stage is about making sure everyone on your team knows what to do next.

Use the Profile Manager to let clients complete key details your team checks during onboarding, such as custom fields for “service type,” “start date,” etc. For multi-seat teams, use task ownership, filters, and internal-only notes to keep each role focused on their responsibilities.

Stage 6: Ongoing communication and check-ins

Establish a reporting cadence early, whether that's weekly, biweekly, or monthly updates. Schedule a 30-day check-in to catch issues before they become problems.

Document everything in one place so nothing gets lost across email threads or scattered tools. Use a shared dashboard or portal so clients can see progress without asking.

Log kickoff notes, questions, and updates directly in the client record. As work progresses, close tasks and update context so the team knows when it's time to move from prep to setup or from setup to review.

Full client onboarding checklist for 2026

A complete onboarding checklist keeps your team aligned and prevents missed steps. Use this checklist to track progress from the first sales conversation through the first few months of work. You can adapt it to match your service model and add or remove steps based on what your clients need.

Download the onboarding checklist.

6 Templates for client onboarding

Templates speed up your onboarding process and keep communication consistent across every new client. Instead of writing the same emails or recreating the same forms from scratch, you can adapt pre-built templates to match your service model and client needs.

Here are six templates that cover the most common onboarding touchpoints:

1. Pre-onboarding template (client qualification form): Use this during the sales process to capture scope, budget, timeline, and technical requirements before the contract is signed. This information shapes how you set up the client later.
2. Contract and payment template (service agreement outline): Start with a structured service agreement that covers scope, deliverables, payment terms, and timelines. Customize it for each engagement so the contract reflects what you actually agreed to.
3. Welcome template (client welcome email): Send this right after the contract is signed to set expectations and outline next steps. Include your team introduction, communication preferences, and what the client should do first.
4. Intake template (information gathering form): Collect the details you need to start work without endless back-and-forth emails. Customize fields based on your service type, whether you need brand assets, access credentials, or business background.
5. Kickoff template (meeting agenda): Structure your first client meeting to cover introductions, project scope, communication preferences, and immediate next steps. This keeps the conversation focused and productive.
6. Ongoing template (30-day check-in email): Schedule a follow-up to catch issues early and show you're paying attention. Ask about their experience so far and if anything needs adjusting.

In Assembly, you can store these templates in shared folders so your team accesses the same versions. Use the Forms app for intake questionnaires, the Tasks app for checklists, and the Messaging app for email templates. This keeps everything in one place instead of scattered across different tools.

Download the onboarding templates.

Typical client onboarding mistakes to avoid

Even experienced service businesses make onboarding mistakes that create problems weeks or months later. I've made these myself, and I've seen people repeat the same patterns. Here are the most common ones and how to avoid them:

Client onboarding best practices

The difference between smooth and chaotic onboarding usually comes down to a few specific habits. I've seen firms cut their onboarding time in half and improve retention just by implementing three or four of these practices. Start with the ones that address your biggest pain points:

• Create the client record before inviting them: Set up the client in your system, upload contracts, prepare file folders, and add internal notes before sending the portal invitation. This lets you control what the client sees on day one instead of inviting them into an empty workspace.
• Use automations to reduce manual work: Automate welcome emails, form assignments, and invoice creation based on client actions. When a client accepts their invite, trigger the intake form automatically. When they submit the form, create the first task for your team. I started with two automations in my own process and now have seven running without thinking about them.
• Assign a single point of contact: Clients shouldn't have to figure out who to email for different questions. Designate one account manager who owns the relationship, even if specialists handle specific deliverables. The confusion I've noticed from "email whoever's available" setups isn't worth the flexibility.
• Send a welcome packet (physical or digital): A welcome packet reinforces that the client made the right choice. Include a brief team intro, your process overview, contact information, and 2-3 case studies. I prefer digital because it's easier to keep updated.
• Schedule a 30-day check-in: Schedule a check-in 30 days after kickoff to ask how the process is going, address any friction, and adjust communication or workflows if needed. 
• Ask for feedback and iterate: Send a short survey after onboarding is complete. Ask what worked, what was confusing, and what they wish had happened differently. Even 3-4 responses will reveal patterns worth addressing.
• Document your onboarding playbook: Write down every step of your process, including who owns each task and what triggers the next action. This becomes training material for new team members and helps you spot inefficiencies. I resisted doing this for years and regret not starting sooner.
• Build in buffer time for delays: Clients will miss deadlines for submitting access credentials, approvals, or required files. Add 3-5 extra days to your internal timeline between kickoff and the first deliverable. I learned this the hard way after missing delivery dates on projects where the work was done, but the client hadn't submitted what we needed.

Want to onboard clients without rebuilding your process every time? Try Assembly

Learning how to onboard new clients takes planning, but many firms still juggle spreadsheets, email threads, and disconnected tools to track contracts, intake forms, and communication. Each new client means rebuilding the same process from scratch.

Assembly is a branded client portal software tool built for service firms that need one place to handle intake, communication, billing, files, and ongoing delivery. It gives you a structured onboarding flow that works the same way for every client while still letting you customize based on engagement type.

Here’s what you can do with Assembly:

• See the full client record: Notes, files, payments, and messages stay in one organized space. You’ll spend less time switching platforms because the key details are already collected for you.
• Prep faster for meetings: The AI Assistant summarizes recent client activity and communication, helping you walk into calls with a clear picture of what’s been discussed and what’s outstanding.
• Stay ahead of clients: Highlight patterns that may show churn risk or upsell potential, making outreach more timely and relevant.
• Cut down on admin: Automate repetitive jobs like reminders, status updates, or follow-up drafts that used to take hours. The Assistant handles the busywork so your team can focus on clients.

Ready to simplify how your firm onboards and manages clients? Start your free Assembly trial today.

Frequently asked questions

How long should client onboarding take?

Client onboarding usually takes 1 to 2 weeks, though complex engagements like software implementation or financial planning can take 3 to 4 weeks. The timeline depends on how quickly clients submit the required information. Assembly helps reduce client onboarding times for our customers by ~75%.

What tools do you need for client onboarding?

You need a client onboarding system for e-signatures, billing, intake forms, file storage, and task management. Many service firms use 4 to 6 different tools to cover these needs, but tools like Assembly combine everything into one system.

What's the difference between client onboarding and customer onboarding?

Client onboarding builds a collaborative service relationship, while customer onboarding guides users to adopt a product independently. Client onboarding includes contract signing, intake forms, and kickoff calls. Customer onboarding focuses on product tutorials and self-service support, though some overlap exists in SaaS products with ongoing relationship management.

What are customer onboarding best practices?

Customer onboarding best practices help users adopt your product independently. Provide in-app tutorials, knowledge base articles, and progress tracking. Send targeted emails based on usage patterns to guide users toward key features. Include onboarding checklists and video walkthroughs so most users succeed without needing help.