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Private AI for answering payroll questions
Short answer
A private AI assistant for payroll gathers the right payslip and the internal decision record for an employee's question, and drafts a reply. The reply describes what follows from the documents, and a payroll specialist checks and sends it. At Syntalith an application on a local model costs from €3,000 net plus GPU hardware. At 400 payroll questions a month of 15 minutes each, it pays back in 1.2 months.
How we workDetails ↓
- 01Call30 minutes with an engineer, free
- 02PrototypeA working system on your process and data, free
- 03ImplementationTarget and fixed price in the contract; 50% at signing
- 04Acceptance50% once the agreed target is met
- model on your server or in the cloud in the EU
- quoted after the review
- same work in application with EU cloud model
- from €3,000
- task, data and equipment analysis
- €0
We belong to the OpenAI and Anthropic partner programmes and learn through their official courses. What this means ↓
Author: Syntalith · 3 min read
Statistics
HR, payroll and AI: statistics 2026
1.2 mo.
payback of a €3,000 local application at 400 payroll questions a month: €3,490 of work today, €1,087 with checking and the GPU server. Scenario.
40%
According to a study published in Science (2023), ChatGPT cut the time 453 professionals spent on writing tasks by 40%.
Source: Noy and Zhang, Science (2023) ↗
52.5%
According to Eurostat (2025), 52.5% of EU enterprises that considered AI but did not use it named unclear legal consequences.
48.8%
According to Eurostat (2025), 48.8% of EU enterprises that considered AI but did not use it named concerns about data protection and privacy.
15.1%
According to Eurostat (2025), 15.1% of people aged 16 to 74 in the EU used generative AI tools for work.
Figures checked: 22 October 2026
A question about a bonus that still waits for a decision
An employee asks why their bonus is missing. The specialist checks the payslip for the period: there really is no bonus on it. In the internal register she sees that the decision has not been made yet. The assistant shows a summary with links to both sources and a draft: „There is no bonus on your payslip for this period. I checked the status: the decision on it has not been made yet.” The reply does not decide what is owed or when it will be paid, and the specialist sees which decision is missing.
Employees describe their questions in their own words: one asks about a missing item, another about a difference from last month. A document from another period does not explain the current question, and a record about another person can never be the basis of a reply, even when it holds the same words. The view links the question to the period and to that person's documents.
- 01Questionthe employee's words and the period it concerns
- 02Payslipthat person's document for that period
- 03Registerthe internal record of the decision, or of its absence
- 04Drafta reply built from what the documents show
- 05Sendingthe specialist checks and sends
What it costs and when it pays back
- Today
- 400 payroll questions × 15 min = 100 h (€3,490)
- With the application, a person checks the output in 25% of the time
- €873
- Hardware in the company, counted in the scenario as a rented GEX45 server
- €214
- Saving
- €2,403 a month
Payback of €3,000
1.2 months
The volume, the time and the checking share are the scenario's assumptions, which we measure in the test. €34.90 an hour is the EU average hourly labour cost for 2025 according to Eurostat. The price of the GEX45 with 24 GB of GPU memory is from Hetzner's website on 22 October 2026, without the one-off setup fee of €209. We price hardware in your own server room after the analysis.
The count covers the time spent searching, reading and putting material together. What remains is the time to check the result against its source, 25% of today's work in the scenario. We measure both times in a test on 20 to 100 cases the team has already handled.
What runs locally and what you have to agree
In the local version, the model runs on a named computer or server. Ollama describes a local mode with the cloud models switched off, but that covers the program that runs the model. A passage from a payslip can stay in the material prepared for search, and case details in a saved draft or a log, so the administrator and the process owner agree access and retention. You also need a person who handles updates and the problem when the application does not show the right document.
- Where the application takes documents from and where it saves results
- What stays in logs, backups and the question history
- Who has access to questions, answers and summaries
- Who updates the model, the application and the document set
What the employee portal can already handle
If the questions are mostly about where to download a payslip or what the fixed descriptions mean, a portal and approved answers are enough. A model is worth considering when the messages vary and a reply needs several records gathered and explained in plain words. The assessment covers the work after the text is generated: checking sources, corrections and preparing the message. The administrative work of HR is described in AI in payroll, and the rules for answers with sources in an assistant on company documents.
Questions about where the payslip is and fixed descriptions
a portal and approved answers
no build
Varied questions, sensitive data
a private assistant for payroll
from €3,000 plus hardware
Questions from HR and documents too
an assistant for HR and payroll with permissions
priced after the analysis
Where to start
The first scope covers one type of question, for example bonuses and allowances, and one person from payroll who judges the drafts. The administrator and the process owner agree access and retention. We deploy local models as part of private LLMs, and we build the view for working with sources as an AI application. For the free analysis, a description of one case and of the places where the material sits is enough. Confidential files stay in the company, and you get a written plan within 2 working days.
Worked example · Scenario
How we count the payback: a payroll team
We run the same count for your team in the free analysis.
€2,908
a month for handling 1,000 employee documents by hand
Payback: 1.2 mo.
5 minutes to receive and check an employee document and checking in 15% of the old time are our assumptions. €34.90 an hour is the EU average hourly labour cost for 2025 according to Eurostat, for companies with 10 or more employees. Model cost: reading a document in our case file system (about €0.0002) plus a description of what is missing (Claude Sonnet 5.5, about 2,000 + 300 tokens), at the ECB rate of 1.1205 USD per euro on 22 October 2026.
See the full calculation →
