Bookkeeping

Simple GoBD-compliant document management directly into DATEV

OS/ makes it easy for you to drastically reduce your accounting workload.

Imagine a world where invoices are checked and approved almost automatically and find their way into your financial accounting software. Reduce your workload by up to 75%! ‍ Book your no-obligation demo

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Diagramm zur BWA & Forecast Analyse für Musterfirma nach Monaten mit Linien für Gesamtleistung, Gesamtkosten und Ergebnis von Februar 2021 bis Mai 2022.

Projektübersicht mit ID, Fortschritt, Status, Team, Umsatz, verrechneten Kosten, tatsächlichen Kosten, Staff, Freelancer, Vendor und Gewinn in einer Budget-Tabelle.

Financial Accounting

Everything about accounting with OS/

GoBD

OS/ takes data protection and compliance very seriously and is fully GoBD-compliant.

All your data and processes within OS/ comply with the strict GoBD guidelines.

AI capture

Forget typing. OS/'s new OCR analysis uses state-of-the-art AI to capture receipts fully automatically.

Just upload and you're done. An intelligent flow that gives you valuable time for your projects. Accounting that simply thinks for itself.

DATEV

With OS/, you can easily create GoBD-compliant outgoing invoices and transfer them directly to DATEV if desired.

Forget about additional financial software or accounting tools! With OS/, you'll find everything in one place, and your data will automatically be sent to your tax office.

DMS

OS/ also functions as an efficient document management system (DMS).

With OS/, you can easily manage and organize your documents. Enjoy a clear structure, fast access, and high security for all your invoice documents.

Flexible billing

Whether it's advance payments, partial final invoices, item-related, time-based, or third-party cost invoices—with OS/ you can handle everything effortlessly and issue e-invoices directly.

Credit Cards

Already using Pleo for your expenses or thinking about it? Perfect—because together with OS/, your accounting will be a breeze.

All about Pleo

Jetzt OS/ 4 Wochen unverbindlich testen.

Teste OS/ kostenlos und unverbindlich mit deinem gesamten Team, vollem Funktionsumfang und kostenlosem Support...

Are you looking for a consultation? No problem, just check here for an appointment:

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Smart Integrations

Von der Ausgabe bis zur FiBu

Wir von OS glauben, dass jedes Unternehmen sein perfektes Software-Ecosystem nutzen sollte, statt sich auf den Kompromiss einer All-in-One-Lösung einzulassen.

Entdecke unsere Integrationen oder lass dir in einer persönlichen Demo zeigen, wie perfekt OS/ mit euren Wunschtools zusammenarbeitet.

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Can't find the solution you need? No problem, let's talk!

Easy to use and
implement

OS/ is very easy to implement in your company.‍

The clear and intuitive interface ensures that your account and project managers can find their way around super quickly and are happy to use OS/.

Most other team members don't work with OS/ at all, but only use the voice time tracking feature in my OS/ or track their time in awork.

Fair: Every software implementation has its rough edges. Our Customer Success Team will help you in less than three minutes. That's a promise.

Why did Parasol Island choose OS/?

With OS/ and DATEV, we generate €21 million in revenue and process more than 8,500 documents per year with 1.5 accounting staff...

Melanie FischerHead of Accounting, Parasol Island GmbH

How accounting works with OS/

Step 1

Invoice Capturing

Writing and recording invoices finally feels as easy as it should with OS/.

Integrated intelligence understands your receipts immediately, while the connection to Google Places adds new supplier data almost automatically.

The same applies to your outgoing invoices: whether they are advance or final invoices, OS/ follows your workflow so that you can get back to what matters faster.

Step 2

Approvals

Quality is created directly in the process. Project management and accounting jointly release documents in OS/.

This guarantees GoBD-compliant data without endless queries and ensures that only perfect documents find their way into accounting.

Step 3

Accounted for instead of just recorded

Before your data leaves OS/, it is automatically completed.

Cost centers, bank details, and booking details are placed exactly where they belong. This saves you tedious rework in DATEV and ensures everything is in order before your tax advisor even reads the first line.

Step 4

Direct connection to DATEV

OS/DATEV Online Integration enables OS/ to transfer your invoice data directly.

Once approved, the data is immediately available to you and your tax advisor. Without any exports or manual intervention, the exchange of information becomes a breeze—this greatly simplifies collaboration and noticeably speeds up your entire accounting process.

Screenshot einer Budgetverwaltungssoftware mit einer eingereichten Rechnung vom 4. Dezember 2025, Details zu Lieferant, Rechnungsnummer, Status, Zahlungs- und Rechnungsdatum sowie Projektauswahl für einen Betrag von 36 Euro.

E-Mail-Benachrichtigung mit dem Text: 'Eine Quittung wartet auf Genehmigung' und einem roten Button 'Open OS25_ADM01'.

Benutzeroberfläche eines CRM-Systems zeigt Kontaktdaten der Firma Monday.com LTD mit Auswahllisten für Kontaktgruppe, Business-Relation als Lieferant und Freelancer, sowie Kontonummern und Adressdetails.

Screenshot einer Kontaktdaten-Verwaltungsseite für Monday.com LTD mit Feldern für Firmendetails, Kontoführung, Adressen und Verantwortliche.

Passt OS/ zu euch? Finden wir es heraus.

Sebastian Druschel, CPO OS/ Agentursoftware

Wir geben dir einen gezielten Einblick, beantworten das Wichtigste und machen dich startklar für deinen Testaccount.

Security & Compliance

Your data is in safe hands

Enterprise Security

At OS/, we take the protection of your data very seriously.

Security and reliability are ensured by regular backups and constant checks and improvements to our infrastructure by the renowned SySS GmbH.

Siegel mit deutschem Flaggenbogen und drei gelben Sternen, mit dem Text GoBD konform, GDPdU konform und Hinweis auf Einhaltung der fiskalischen Vorgaben der digitalen Betriebsprüfung in Deutschland.

Compliant

We rely on professional hosting and high-quality infrastructure products from AWS, the undisputed market leader.

Our servers are located 100% in Germany.

GDPR/DSGVO

OS/ is GoBD-certified and our platform is fully compliant with EU data protection laws.

You can find details in our data protection section.