Onboarding a New SME Client: The First 30 Days Playbook

The contract is signed. The client is excited. You're already thinking about the next three clients in the pipeline.

And then day 12 arrives, and you realise you don't have half of what you need to close their first month. The NIF from the prior accountant never came. You're still waiting on access to a supplier portal. Three recurring invoices went straight to the client's personal email because nobody told them where to forward things. You spend two hours on a Saturday reconstructing a month that should have been routine.

The first 30 days with a new SME client are the quietest moment you will ever have to set the relationship up properly. Miss the window, and you inherit chaos for the next five years.

What the First 30 Days Actually Are

Onboarding is not "collecting documents and adding the client to the billing system." That's administration. Onboarding is the process of installing — in the client's habits, inboxes, folders, and calendar — the workflow that lets you close their month in two hours instead of two days. Our complete guide to invoice automation covers the tooling side of that workflow in detail.

You only get the client's full attention once. They are motivated now because they just switched accountants, or just started the business, or just got burned by whoever was doing this before. In six weeks they will be heads-down on their actual business and will stop answering your WhatsApps within 24 hours. Use the attention while you have it.

Three goals for the first 30 days, in order:

1. Complete visibility. You know every channel their invoices arrive through, every supplier portal, every recurring charge.
2. One drop-off point. There is exactly one place the client puts new invoices. Not three. One.
3. A working close for month one. By day 30, you have closed one full month under the new system and identified what broke.

If you hit those three, everything else is cleanup.

Week 1 (Days 1–7): Discovery

The temptation in week one is to send the client a long document request and wait. Don't. The client will send you 60% of what's on the list and you'll spend week two chasing the rest. Instead, treat week one as a discovery interview — their business, as it actually runs — not a compliance intake.

Day 1–2: The real kick-off call

Block 60 minutes. Not 30. Not async. On video, screen share on their side.

Ask them to show you, live:

• The email inbox where invoices arrive. Scroll through the last 30 days.
• Every supplier portal they log into — EDP, Vodafone, NOS, landlord portal, whatever else.
• Where paper invoices physically go. The shoebox, the drawer, the assistant's desk.
• Their bank statement from last month, line by line. Every charge you can't identify is a hidden supplier.

You will find three to five invoice channels they forgot to mention in the proposal stage. That's normal. Write them all down.

Day 3–5: Document collection, but scoped

Now send the document request — but only what you actually need to start. NIF, tax regime, certidão permanente, social security, prior accountant handoff (SAF-T files from the last 12 months if possible), bank authorisation for debits, Portal das Finanças sub-user access.

Do not ask for three years of invoices on day three. You do not need them yet, and asking for everything at once is how the client decides the onboarding is "too much" and goes quiet.

Day 6–7: Prior accountant handoff

This is where most onboardings silently go wrong. The outgoing accountant is technically obliged to hand over records, but "obliged" and "prompt" are different words. Send a formal written request with a deadline. CC the client. Ask specifically for:

• The last 12 months of SAF-T-PT files
• Chart of accounts as currently used
• Any open reconciliations or carried-forward balances
• The list of suppliers and customers with their NIFs already validated

If you don't have the SAF-T files by day 10, escalate. Waiting until day 25 to discover the prior accountant is unresponsive is how you end up filing the first month blind.

Week 2 (Days 8–14): Setup

By now you know what the client's month looks like. Week two is where you build the infrastructure before any real invoice processing happens.

Day 8–10: The shared folder and the one rule

Create the folder structure. A simple one works:

ClientName/
├── Entregue/        (invoices the client drops here)
├── Processado/      (once you've booked them)
├── Dúvidas/         (things you need to ask about)
└── Referência/      (contracts, certidão, chart of accounts)

Share Entregue with the client. Share the others read-only or keep internal. Then have the single conversation that matters: every invoice, within 24 hours of arrival, goes into Entregue. Not email. Not WhatsApp. Not "I'll send them all at the end of the month." One place, one rule.

If the client cannot commit to this single habit in week two, the rest of the year will be you chasing. Be direct about it now — it's easier to reset expectations on day 10 than on day 210.

Day 11–12: Email forwarding and portal downloads

For channels the client can't change overnight, bridge them:

• Email invoices: set up a forwarding rule from their main inbox to a dedicated alias (e.g., [email protected]) that drops into the shared folder via a connector, or into a processing inbox you monitor.
• Supplier portals: list every portal, assign an owner (usually the client), and put a recurring calendar reminder on the 3rd of each month to download last month's PDFs into Entregue.
• Paper invoices: phone camera, straight upload. Tell them blurry is fine — you'd rather have a photographed invoice on the 5th than a pristine scan on the 30th.

Day 13–14: Tracking and expectations

Set up one visible tracking sheet — Google Sheets works — with columns for date, supplier, status (Entregue / Processado / Em falta), and notes. The client sees it. You see it. When something is Em falta, everyone knows without a WhatsApp.

And set expectations in writing: what you need by when, what the client owns, what you own, what the monthly rhythm looks like (e.g., "I process every Tuesday and Thursday; the month closes on the 8th"). Email it. They won't read it all, but you'll need it in month four when something slips.

Week 3 (Days 15–21): First processing cycle

This is the week you start actually working their invoices. Do not try to catch up on three prior months yet — close the current month first, then go back.

Day 15–17: Chart of accounts and recurring supplier mapping

Take the suppliers from the prior accountant's files (if you got them) and from the bank statement. For each recurring supplier:

• Confirm the NIF (validate it — one transposed digit causes SAF-T headaches for years).
• Map them to the correct chart-of-accounts account.
• Flag the typical VAT rate. Portugal has three IVA rates plus exemptions, and suppliers classify themselves inconsistently.

This takes a few hours now and saves a multiple of that every month going forward. Manual supplier setup at entry time is where most SAF-T mismatches are born — see our SAF-T survival guide for what AT actually checks.

Day 18–21: Process the current month

Now process the first month's invoices under the new workflow. Two things to watch:

1. Where did invoices come from? If 20% arrived via a channel that isn't the shared folder, the workflow isn't working yet. Talk to the client before week four, not at month three.
2. What's missing? Cross-reference against e-fatura and the bank statement. If the bank shows a direct debit from a supplier whose invoice never appeared, that's the conversation to have now — while the client still remembers what that €147 charge was for.

Week 4 (Days 22–30): Close and retrospective

The first close under a new system always has surprises. The goal of week four is not a perfect close — it's a diagnosed one.

Day 22–26: Close the month

Reconcile, validate, submit SAF-T. Keep notes on what was painful: which suppliers sent invoices late, which portals nobody remembered to check, which invoices had NIF mismatches. If you are handling multiple clients with SAF-T, our monthly SAF-T automation walkthrough covers where to insert automation without losing control.

Day 27–28: Retrospective with the client

Book a 30-minute call. Not an email summary — a call. Cover three things:

• What worked. Tell them the specific invoices that arrived on time and why that helped.
• What slipped. Be concrete: "Three EDP bills came in on the 28th. Next month I need them by the 10th." No blame, just the gap.
• What needs to change for month two. Usually one or two habits, not a redesign. Pick the smallest change that fixes the biggest gap.

Clients respect accountants who diagnose. They disengage from accountants who just complain on WhatsApp.

Day 29–30: Internal retrospective

You also need a retrospective with yourself — or your team, if you have one. Document, for your own files:

• Channels and portals for this client
• Recurring suppliers and their VAT categories
• Known gotchas (the one that always arrives late, the one with the weird NIF, the one the client forgets)
• Estimated monthly processing time under the new workflow

This becomes your onboarding template for client number two, three, and ten. Every new SME you bring on reuses 80% of this.

What to Do Differently

Most accountant onboardings fail for the same reason: week one is about paperwork, and the actual workflow conversation happens in month three, when everyone is already frustrated. Flip it. Use week one for discovery, week two for workflow, week three to run it, and week four to diagnose. The paperwork slots in around those, not the other way around.

And accept that the first month will not be clean. It is not supposed to be. It's supposed to tell you — and the client — what needs to change before month two.

If your onboarding playbook is mostly "send a document list and hope," a workflow-first approach closes months faster and keeps clients from going quiet at month three. Faturiza is built for accountants running this playbook across multiple SME clients — one shared folder per client, automated data extraction, SAF-T-ready export. Free during beta, designed to drop into the workflow above rather than replace it.