Process Automation Cost for SMEs: A Worked Example

The question usually arrives in one line: "what does process automation cost?" The honest answer is that it depends, but not in a mysterious way. It depends on four things you can count before you ever ask for a quote.

This article walks through those four things, separates the one-off cost from the monthly cost, and runs the numbers on a real case: processing supplier invoices in a Portuguese SME.

There are two costs, and only one appears in the quote

Automating a process has an implementation cost, paid once, and a running cost, paid every month.

A consultancy quote almost always covers only the first. The second (licences, hosting, AI usage, maintenance) sits with the company. If you only compare implementation quotes, you are comparing half the cost.

What drives implementation cost

Implementation effort is measured in hours. The hours depend on four factors:

Number of steps in the workflow. A five-step flow does not cost the same as a 25-step one.
Number of integrations. Every new system (ERP, CRM, email, a shared folder) brings its own authentication, data formats and errors.
An AI layer. Reading a PDF invoice, classifying an email or drafting a reply needs prompts, testing on real documents and rules for when the AI gets it wrong.
Rules and exceptions. This is where projects overrun. The happy path is quick. The invoice with the wrong VAT number, the supplier who sends it twice or the approval that stalls take longer.

On top of that come analysis and design, testing with your team, go-live and documentation. A serious proposal lists each phase separately, with its own hours. If you get a single number with no breakdown, ask for one.

Three orders of magnitude

Based on those four factors, these are our effort estimates for typical SME projects. They are estimates of work, not a price list. The final figure depends on the hourly rate of whoever builds it.

Simple flow, no AI: 10 to 20 hours. Example: a contact form on the website creates the customer in the CRM and sends a confirmation email. Two systems, simple rules, few exceptions.
Mid-sized flow with AI: 40 to 60 hours. Example: invoices received by email are read, validated and posted to the ERP. Three or four integrations, AI data extraction and a human review queue.
Complex flow: 80 to 150 hours or more. Example: an order process that crosses sales, warehouse and invoicing, with approvals and many exceptions. Splitting it into phases usually pays off.

Project management is added on top, typically as a percentage of the implementation hours.

The monthly cost: platform, AI and maintenance

Running costs are lower than many decision-makers expect, but they are not zero.

Automation platform. On the n8n Cloud Starter plan, the price is €20 a month, billed annually, for 2,500 executions a month. Pro costs €50 a month for 10,000. The alternative is self-hosting the n8n Community edition: there is no licence fee, but you pay for the server (a small virtual server from a European provider starts at around €6.50 a month excluding VAT) and you own updates and backups.

Pricing models matter. n8n charges per execution. Power Automate Premium charges $15 per user per month. With few users and many executions, one model wins; with many users, the other does. We covered this in our piece on what n8n is and how per-execution pricing works.

AI usage. If the workflow uses a language model, you pay per token processed. On Anthropic's API pricing page, Claude Sonnet 5.5 costs $2 per million input tokens and $10 per million output tokens. For short documents, that is cents per document, not euros.

Maintenance. APIs change, suppliers alter their formats and exceptions nobody predicted turn up. It is sensible to set aside a few hours a month for a workflow in production. That is our estimate, but a workflow without an owner eventually breaks without anyone noticing.

Worked example: automating 300 invoices a month

Take a concrete case. An SME receives 300 supplier invoices a month. Each takes 4 minutes to open, check and post to the ERP.

Current cost of the manual process

300 invoices × 4 minutes = 20 hours a month.
In 2025, according to Eurostat labour cost data, an hour of work cost Portuguese businesses €19.40 on average, including employer charges.
20 hours × €19.40 = €388 a month.

If you want to run this calculation on your own processes, the full method is in our article on how much manual processes actually cost.

After automation

AI extracts the data and the workflow posts the invoice. A person reviews each one in about a minute: 5 hours a month.
Saving: 15 hours × €19.40 = €291 a month.

Monthly cost of the automation

n8n Starter: €20 a month. 300 executions fit comfortably within the plan's 2,500.
AI: assuming 5,000 input tokens and 500 output tokens per invoice on Claude Sonnet 5.5, each invoice costs about 1.5 US cents. 300 invoices come to roughly $5 a month.
Net saving: about €265 a month.

Implementation

This is a mid-sized flow with AI. Estimate: 44 hours (8 for analysis and design, 24 for development and integrations, 8 for testing, 4 for go-live and documentation), plus project management.

For the investment to pay back within 12 months, implementation should cost no more than about €3,200 (€265 × 12). Over 24 months, the ceiling rises to about €6,400. That is the number to hold quotes against, rather than a gut feeling about what "seems expensive".

The same process pays back more slowly in Portugal

International articles on process automation cost rarely mention this. An hour of work in Portugal costs just over half the European average: €19.40 against €34.90 across the EU in 2025, in the same Eurostat series.

The 15 hours saved in the example are worth €291 in Portugal and €523 in a company at the EU average cost. The same project, at the same implementation cost, pays back almost twice as fast elsewhere.

The practical consequence is that volume carries more weight in the decision here. If the same company received 30 invoices a month, the saving would be about €29 a month. After paying for the platform, almost nothing would be left. In that case automation does not pay for itself, and a good consultant should say so.

Costs that appear nowhere

Some real costs are neither in the quote nor on the monthly bill:

Your team's time. Someone has to explain the process, supply real examples, test and sign off. Budget several hours from a person who knows the process well.
Data quality. If suppliers in the ERP are duplicated or out of date, the automation will stumble. Fixing data at source is separate work.
Changing habits. For the first few weeks the team will distrust the output and check everything. That is normal, but it delays the saving.

Where to start

The cheapest way to automate is to pick the first process well. Look for high volume, stable rules and few systems involved. Our list of 20 business processes every company should automate has concrete candidates by department.

Before asking for quotes, do one simple sum: how many hours a month the process takes and what each hour is worth. If the annual net saving does not cover the process automation cost within one or two years, it is not the right process yet.

Which process in your company eats the most hours every month, and do you know how many it is?