When is custom software cheaper than SaaS?

The real cost is rarely the sticker price

SaaS looks cheap at the start because the monthly fee is easy to approve. Cost grows when teams add users, unlock premium features, connect integrations, and keep overlapping tools alive.

How to calculate the break-even point

Use a simple model before making the decision. Add licence costs, integration costs, manual work caused by tool limitations, and expected price increases. Compare that with build, hosting, and maintenance.

• List every subscription the custom tool would replace.
• Add the monthly cost for all active users.
• Estimate time lost to duplicate data entry or workarounds.
• Divide the build cost by the monthly saving.
• Add yearly maintenance before making the final call.

When SaaS is still the better choice

SaaS is often right for early experiments, very small teams, and commodity processes. Custom software becomes interesting when a workflow is strategic, repeated daily, or expensive because it touches many people.

Decision framework for SME software

Do not make software decisions from tool preference alone. Compare process value, data risk, maintenance, and ownership. For growing companies, the best choice is often not the cheapest licence, but the system that permanently reduces manual work and dependency.

Lower-risk implementation route

A strong software decision starts small. Do not replace the whole landscape at once; choose a workflow with visible upside and manageable migration risk.

• Inventory costs, users, and duplicated entry.
• Choose one workflow with a clear owner.
• Build the smallest version people use daily.
• Migrate data with validation and a parallel period.
• Measure time saved, errors reduced, and adoption.

Compare total ownership cost, not the monthly licence

A SaaS subscription looks predictable, but the real bill includes licences, implementation, integrations, administration and the work people still do outside the product. Custom software makes more of the investment visible upfront, while usage costs can remain flatter as the company grows. Compare both options over at least three years and apply the same assumptions for user growth, transaction volume and future changes.

• Include every module, user tier, storage fee, transaction charge and support plan.
• Put a value on duplicate entry, manual checking and workarounds.
• Budget for hosting, security, maintenance and product development after launch.
• Model a steady case, a growth case and a material process-change case.

Example: replacing five tools with one operating platform

A service business runs a CRM, scheduling product, customer portal, document store and reporting tool. Subscriptions cost EUR 5,800 a month, while staff spend about 120 hours copying and reconciling information. A custom platform costs EUR 135,000 to build and EUR 2,500 a month to operate and improve. The financial break-even sits around year three. The larger benefit is a single workflow, fewer errors and business data the company can use without negotiating access with five vendors.

Build a defensible build-versus-buy decision

Do not start with a feature wishlist. First identify what is genuinely distinctive about the process, which information is strategic and where standard software demonstrably fails. A short discovery with users and decision-makers prevents a custom project from becoming an expensive copy of an existing product.

• Map the current process, exceptions, systems and owners.
• Separate commodity features from business-specific logic.
• Create a 36-month cost model using consistent assumptions.
• Test the largest technical uncertainty with a focused prototype.
• Decide module by module whether to buy, connect, replace or build.

Measure value after launch

Software is not successful simply because it works. Record a baseline before development and check after each release whether the operation is actually becoming easier. This keeps the roadmap tied to business outcomes rather than feature count.

• Total software cost per employee, customer or transaction.
• Lead time from request to completion.
• Manual hand-offs, corrections and support requests.
• Adoption: the share of the target process completed in the new platform.

When SaaS remains the better choice

Do not commission custom software for a generic process that a mature supplier handles well at a fair price. SaaS is also safer for a small team, unstable requirements or a business without product ownership. Custom development becomes attractive when the process is stable enough to model, important enough to own and supported by someone who can make product decisions after the first release.

The board-level question behind build versus buy

The decision is rarely financial alone. SaaS buys speed, a vendor roadmap and shared maintenance. Custom software buys control over process, data and future change. Leadership should identify which part of the operation is genuinely distinctive and which dependencies are acceptable. A system that directly controls revenue, customer relationships or capacity deserves a different test from a generic calendar or payroll product. The assessment should also cover what happens if a vendor raises prices, closes an API or cannot support a new market.

• Which workflow directly affects revenue, margin or customer experience?
• Where do employees routinely work outside the current product?
• Which data must remain available without vendor permission?
• How quickly must new locations, products or pricing models be introduced?
• Who will own product decisions and budget after launch?

Use a portfolio of options instead of one large decision

Build versus buy is not binary. Strong architecture uses standard products for commodity capability and builds the layer that creates advantage or joins the operation together. A restaurant can buy accounting and payments while owning reservation rules, guest profiles and multi-site control. A recruitment business can outsource email and identity while bringing ATS, assessment tracking and client workflow into its own platform. Capability-by-capability decisions reduce the first commitment and make later replacement possible without rebuilding the whole business.

• Buy: mature generic capability with heavy compliance or little differentiation.
• Configure: an established product that fits with limited adaptation.
• Integrate: a controlled data and workflow layer between products.
• Build: company-specific logic, experience and automation.
• Retire: duplicate products and workarounds removed after adoption.

Evidence required before investment

A sound decision needs more than a supplier quote. Gather current invoices and active-user data, measure manual effort and test whether information is completely exportable. The technical option should include security, integrations, support and migration. A custom route also needs a limited first release with acceptance criteria and a stop point. This prevents an attractive theoretical payback from being used to justify an oversized programme.

• A 36-month TCO using the same growth assumptions for both options.
• Process evidence covering volume, delay, error and recovery work.
• A practical export and API review of current suppliers.
• A first scope with users, exceptions and explicit non-goals.
• An operating plan for monitoring, security, support and development.