Cloud, SaaS or on-premise – where should your software run?

Cloud or on-premise: pros and cons at a glance

At its core, the question is who bears which responsibility. With on-premise, you run the servers, network, operating system and application yourself – with full control, but also full effort for security, spare parts and emergency planning. With cloud hosting, the provider takes over the data center and hardware, and you concentrate on your application. With SaaS, you also hand off the operation of the software and use only the result.

The benefits of the cloud show up mainly in flexibility and speed: new environments are available at short notice, load peaks are absorbed, and locations can be distributed. On-premise plays to its strengths with stable utilization, local data processing and connections to production equipment. With your own servers, the effort for fault tolerance is often underestimated – spare hardware, tested backups and a recovery plan are mandatory.

SaaS or on-premise: which is cheaper?

There is no blanket answer because the cost structures differ fundamentally. On-premise means upfront investment in hardware, licenses and setup, plus ongoing costs for power, maintenance, staff and regular hardware replacement. SaaS and cloud, by contrast, cause ongoing operating costs that grow with the number of users or usage. So always compare the total cost over several years (total cost of ownership) rather than just the first invoice.

The calculation should also include factors that rarely appear on a price list: internal working time for administration, the cost of downtime, the effort for security updates and training, and the cost of a later switch. With SaaS, price adjustments or new plan models can change the calculation; with on-premise, a hardware replacement comes due after a few years. Anyone who assesses these points honestly makes a decision that holds up in the long run.

Self-hosted, private cloud and hybrid: the in-between models

There are mixed models between the three basic ones. Self-hosted means that you run a piece of software yourself – whether on your own servers or on rented cloud infrastructure. Many open-source tools such as n8n, Nextcloud or ticketing systems can be used this way instead of subscribing to the SaaS version. A private cloud provides cloud capabilities such as virtualization and self-service exclusively for one company, in its own or a dedicated data center.

In practice, many mid-sized companies (Mittelstand) rely on a hybrid model: email and collaboration as SaaS, their own customer platform in the cloud, the production system on site. What matters then is that the systems are connected via clean interfaces and that users, permissions and backups are managed centrally. ERP, too, increasingly raises the question of “on-premise or cloud,” because many vendors are putting their cloud versions front and center.

Data privacy and data sovereignty: what matters

For the GDPR, the operating model is not what matters, but where and under what contract personal data is processed. With cloud and SaaS, you need a data processing agreement, clarity about server locations and, for providers based outside the EU, a review of data transfers. Many large providers operate data centers in Germany, and there are also European providers such as Hetzner, IONOS or STACKIT.

On-premise does not automatically solve the data protection question: your own servers must also be encrypted, patched, monitored and protected against failures. For smaller companies, the security level of a professional data center is hard to reach on their own. So clarify early with your IT team and, if applicable, your data protection officer which data needs how much protection. This overview does not replace legal advice.