The finance tool stack for growing companies: Which tools you really need

Anyone starting a company faces dozens of operational decisions in the first few weeks. Which bank account? Which credit card? How do invoices get sent out? How do receipts get to the tax advisor? Most founders solve these questions pragmatically and one by one, depending on what is on fire at the moment. The result is often a patchwork of tools that do not talk to each other and whose data has to be painstakingly gathered at the end of the month.

It does not have to be that way. With a well-considered selection of four to five tools, you can build a finance setup that works from day one, is cleanly connected to the accounting firm, and can support you through several growth phases. The effort involved is manageable, provided the setup is done properly.

Why the setup matters at the beginning

The temptation to postpone finance topics until later is strong. As long as the company is small, a bank account and an Excel list are enough. That is true, but only in the short term. The decisions made in the first few weeks determine the quality of the data for months and years.

A company that has clean digital data flows from the start benefits in three ways. First: ongoing bookkeeping becomes faster and cheaper because less manual follow-up work is needed. Second: the tax advisor can provide proactive advice instead of chasing receipts after the fact. And third: when the company grows and the first employees start making expenses, there are already processes in place that work.

The downside is just as real: anyone working without structure in the first months builds up technical and organizational debt that will be expensive to fix later. Missing receipts, transactions that cannot be assigned, and unclear cost structures become harder to reconstruct with each passing week.

The foundation: a business account that fits the accounting firm

Every company needs a business account. The choice of the right account depends less on individual features than on two factors: integration with DATEV and the existing banking relationship.

Traditional banks such as Sparkasse, Volksbanken, or Deutsche Bank work smoothly in the DATEV ecosystem. Account transactions can be retrieved automatically via the DATEV bank data service (EBICS or PIN/TAN method) and processed in DATEV Unternehmen Online. For many companies that already have a relationship with an institution, for example through a private account or an existing business contact, this is the easiest route.

Neobanks like Qonto are an alternative, especially for founders who value a modern interface, fast account opening, and integrated receipt management. Qonto is an official DATEV marketplace partner and offers several interfaces: the bank data service via PIN/TAN (finAPI), the receipt image service, and the invoice data service 1.0. In practice, the integration works, but it requires more initial configuration than with a traditional bank. There are also limitations, for example with batch payments via DATEV Unternehmen Online and the fact that not all interfaces are available in the cheapest plans.

The honest recommendation: if the banking relationship is a good fit and the traditional bank supports EBICS, there is no compelling reason to switch. If you are starting fresh and do not already have an account, Qonto is a solid option with a good price-performance ratio. In both cases, the DATEV integration should be set up from the beginning, not only at the first annual closing.

One important point that applies regardless of the chosen account: ideally, the business account should mainly be used for bank transfers and SEPA direct debits. Card payments, meaning everything from software subscriptions to business lunches to travel expenses, should be handled as early as possible through a separate card system. This creates transparency and avoids the situation where credit card transactions appear on the account at the end of the month without matching receipts.

Card payments and expense management: Moss

As soon as more than one person in the company is making expenses, a system for card payments and expenses becomes a necessity. Moss has established itself as one of the strongest providers in the German market here, and for good reason.

With Moss, physical and virtual Mastercard credit cards can be created for individual employees or projects. Each card can be given individual budgets and approval workflows. The managing director gives the sales manager a card with a monthly limit of 2,000 euros, the marketing manager gets a virtual card for the Google Ads account, and a temporary card with a defined budget is created for the next trade fair. All in one interface, trackable in real time.

The real value of Moss, however, is not in issuing cards, but in preparing the bookkeeping. Employees photograph receipts via the app, OCR recognition reads amounts, dates, and tax rates, and the expenses are automatically assigned to the correct cost centers and general ledger accounts. At the end of the month, the entire batch is exported via the DATEV interface. Moss is an official DATEV interface partner and GoBD-certified. The standard integration via DATEV Unternehmen Online is included in all plans.

In practice, this means that instead of the bookkeeper matching credit card statements with loose receipts at the end of the month, the data is already coded and linked to receipt images. The time savings are considerable, especially for companies with ten or more cardholders.

Outgoing invoices: Easybill

Anyone who writes invoices regularly will quickly reach the limits of Word templates or Excel. Invoicing software brings structure to the process, automates recurring billing, and, since the e-invoice requirement (from January 2025 for B2B transactions), ensures compliance with the XRechnung and ZUGFeRD formats.

Easybill is a pragmatic choice here. The cloud-based software covers invoices, quotes, delivery notes, and reminders, and offers a range of functions that is more than sufficient for most growing companies without becoming as complex as an ERP solution.

What matters in the accounting-firm context: Easybill is an official DATEV marketplace partner. Through the invoice data service 1.0, outgoing invoices, including receipt image and posting proposal, are transferred directly to DATEV Unternehmen Online. The tax advisor receives ready-made document sets that only need to be checked and posted. Exports can be carried out daily, not just monthly, which significantly improves the timeliness of the data.

In addition, Easybill offers tax advisor access. The accounting firm can access the data directly, review account assignment mappings, and make corrections if necessary without the client having to do anything. Anyone active in e-commerce also benefits from more than 50 shop integrations (Amazon, Shopify, eBay, and others), through which orders are automatically turned into invoices.

DATEV Unternehmen Online: the hub

None of the tools mentioned reaches its full value without the right integration with the accounting firm. DATEV Unternehmen Online (DUO) is the system where all data flows come together: bank transactions from the bank, outgoing invoices from Easybill, card transactions from Moss, and manually uploaded incoming receipts.

Many entrepreneurs shy away from DUO because the interface does not match what they are used to from modern SaaS products. That is understandable, but it is not a reason to skip the setup. In day-to-day operations, the client only needs DUO for a few tasks: uploading receipts (via the upload app or receipt transfer), submitting missing receipts, and occasionally reviewing reports. Everything else happens in the background, triggered by the connected tools.

The key point: setting up DUO is not automatic, but it is also not rocket science. With the right support from the accounting firm, the setup can be completed in one or two appointments. The firm sets up the client base, configures the processing mode (Standard or Extended), connects the bank accounts, and activates the data services for third-party providers such as Moss and Easybill. After that, the data flow runs largely automatically.

Personnel and travel expenses: HRIS and side solutions

As soon as the first employees are on board, the company needs a system for personnel management. The choice of HRIS (Human Resources Information System) has a direct impact on payroll accounting, because here too data must flow in a structured way to the accounting firm.

Personio has established itself in German mid-sized businesses as the standard for HR management and offers a DATEV Lodas interface for payroll data transfer. For growing companies, it is often the right choice because it combines recruiting, onboarding, absences, and payroll in one platform. Alternatives such as HRworks or Kenjo can be sufficient for smaller teams and also come with DATEV integrations.

If your team travels a lot, it is worth taking a look at specialized travel management tools such as Lanes & Planes or Navan. These make it possible to book flights, hotels, and rental cars within defined travel policies. The DATEV integration is not always perfect with these tools, but the bookkeeper can log into the system and export the relevant data. For companies with regular travel activity, this saves a great deal of time compared with manual travel expense reports.

The big picture: how the tools work together

Once the setup is in place, the monthly workflow looks roughly like this: bank transactions are automatically pulled into DUO via the bank data service. Outgoing invoices flow from Easybill to DUO via the invoice data service. Card transactions and expenses are approved in Moss and transferred via DATEV export. Incoming receipts not covered by one of the tools are uploaded to DUO via the upload app or receipt transfer.

On the accounting firm side, all relevant data is then available: posting proposals with linked receipt images, structured by incoming and outgoing invoices, bank movements, and credit card transactions. The bookkeeper checks, corrects where necessary, and posts. This not only reduces the workload, but also changes the way collaboration works. Instead of collecting receipts and asking follow-up questions, the accounting firm can analyze the data, identify anomalies, and provide proactive advice.

Looking ahead: integrated platforms

The market is evolving. Providers such as Pennylane follow an integrated approach, in which bookkeeping, invoicing, and banking come together in one platform instead of being connected via separate tools and interfaces. For companies that do not have to or do not want to work in the DATEV ecosystem, this can be an interesting alternative in the long term.

At the moment, however, the German market is still strongly shaped by DATEV: more than 90 percent of tax firms work with DATEV, and any tool change on the client side must be measured against this reality. Anyone building a finance setup today is on safe ground with the combination described here of proven individual tools and clean DATEV integration. And anyone who wants to keep an eye on the market should watch integrated platforms without switching too quickly.

The role of the tax advisor in the setup

Tool selection is one half. Proper setup is the other. And this is where you see what distinguishes a good tax advisor from an average one.

A tax advisor who only gets involved at the annual closing and then complains about missing receipts is not solving a problem. They are documenting it. A good tax advisor starts the relationship with structured onboarding: Which tools is the client already using? Which should be introduced? How should the interfaces be configured? Which processing mode in DUO is the right one?

The first few weeks of a client relationship are therefore more intensive than day-to-day operations. It takes two or three appointments to set up the system together, test the data flows, and show the client the few actions they need to handle themselves in daily use. That effort pays off: once the infrastructure is in place, ongoing collaboration runs with only a fraction of the effort that a poorly set up client relationship would cause.

For the client, this means: look for a tax advisor who actively leads this conversation. Not one who asks whether you use DUO, but one who sets it up with you. Not one who accepts receipts by email, but one who shows you how the data arrives automatically. The quality of tax advice does not begin with the tax return. It begins with the question of how your data gets into the accounting firm.