What custom software costs compared with off-the-shelf SaaS

An off-the-shelf SaaS product typically costs €20 to €300 a month per user or per company depending on the feature set. Custom software requires an up-front investment of €10,000 to €80,000 plus lower ongoing costs for hosting and maintenance. The deciding question is not which is cheaper at the start, because SaaS always wins that one. It is which is cheaper over three to five years, and whether the off-the-shelf product covers your processes at all.

Cost compared over time

Why SaaS looks cheaper and may not be

SaaS platforms price per user or per volume, which means cost rises in direct proportion to the company's growth. A company of five pays a fraction of what a company of a hundred pays for the same tool. For fast-growing B2B companies, SaaS costs over three to five years can therefore climb past the one-off investment in a custom build, with the difference that at the end of it the company owns nothing.

When off-the-shelf SaaS is the right call

• A standardised process – accounting, email marketing, project management and similar processes that work much the same in every company.
• A fast start – you need a solution now, not in several weeks.
• Uncertain future need – you do not yet know whether the company will need this process in this shape long term.
• Low volume or a small team – costs stay low at a smaller scale of use.

When custom software is the right call

• A specific process no off-the-shelf product covers properly – the company bends itself around the software instead of the software serving the process.
• Growing volume of users or data – at larger scale, the one-off investment beats rising monthly fees.
• A need for full control over the data – particularly with sensitive data, where a third-party platform is a security or compliance risk.
• Several systems joined into one workflow – when a company runs five or six separate tools and actually needs one connected system rather than moving data between them by hand.
• Technology as a competitive advantage – if the software is part of what the company offers its clients, an off-the-shelf product cannot differentiate it.

The hidden costs people forget

With SaaS:

• Overage charges for records, API calls or seats.
• Fees for extra integrations or premium features.
• Data migration costs if the company later decides to move elsewhere.

With custom software:

• Ongoing maintenance and updates, typically 15 to 20 per cent of the original investment a year.
• Infrastructure scaling as volume grows.
• The need for a clear agreement on long-term support after go-live. What to ask for is covered in how to choose a supplier.

The hybrid approach is what usually happens

Most B2B companies do not in fact use one approach. Standardised processes run on off-the-shelf tools, while the processes that differentiate the company, or are too specific for a packaged product, are built. A typical example is a custom AI agent sitting on top of an existing SaaS CRM. That combination tends to give the best ratio of cost to value.