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software 2026-03-10 4 min

What Is Custom Software? How to Choose Between Custom and SaaS

Custom software is built specifically for your business needs, unlike SaaS solutions designed for everyone. This article helps you decide which option delivers better value for your situation.

What Is Custom Software? How to Choose Between Custom and SaaS

What Is Custom Software?

Custom software (also called bespoke software) is developed specifically to meet the unique needs of your business — unlike SaaS (Software as a Service), which is an off-the-shelf product shared by many users.

Custom software is a "tailored suit" while SaaS is "ready-to-wear clothing" — the tailored suit fits better but costs more and takes longer to make.


What Is SaaS and Why Is It Popular?

SaaS (Software as a Service) is software accessed via the internet with a monthly or annual subscription fee. Well-known examples:

  • CRM: Salesforce, HubSpot
  • Accounting: Xero, QuickBooks
  • Project Management: Asana, Monday.com
  • HR: Workday, BambooHR
  • E-Commerce: Shopify, WooCommerce

The reason SaaS is so popular is speed to start — sign up today and you're running immediately, no months of development required.


Pros and Cons of Each Option

Custom Software

Pros:

  • ✅ Designed 100% around your specific business processes
  • ✅ No unnecessary features — simple and targeted
  • ✅ You own the source code — no vendor dependency
  • ✅ Full integration capability with existing systems
  • ✅ Lower long-term costs — no perpetual monthly fees
  • ✅ Scales with your business

Cons:

  • ❌ Higher upfront cost
  • ❌ Development takes 2–12 months
  • ❌ Requires expertise to maintain
  • ❌ Risk if you choose the wrong vendor

SaaS

Pros:

  • ✅ Fast to get started
  • ✅ Low upfront cost
  • ✅ Built-in best practices
  • ✅ Automatic updates by the provider
  • ✅ Usually strong support and community

Cons:

  • ❌ Limited customization — you must work within the software's workflow
  • ❌ Monthly fees accumulate significantly over time
  • ❌ Your data lives with an external provider
  • ❌ If the provider shuts down or raises prices, you face a full migration
  • ❌ Features you need may require more expensive plans

Cost Comparison: Custom vs SaaS Over 5 Years

Custom SoftwareSaaS (Enterprise Plan)
Year 1500,000 THB (development)120,000 THB
Year 260,000 THB (maintenance)132,000 THB (+10%)
Year 360,000 THB145,000 THB
Year 460,000 THB160,000 THB
Year 560,000 THB176,000 THB
Total 5 years740,000 THB733,000 THB

These are illustrative figures. The point: custom software is not always more expensive than SaaS over the long term.


Signs You Need Custom Software

Ask yourself these 5 questions:

  1. How unique are your business processes? If your workflow is complex and unlike others, SaaS will force you to change your process rather than supporting it.
  2. Do you integrate with multiple systems? SaaS integrations are often limited. If you need to connect many systems, a custom solution is more flexible.
  3. How sensitive is your customer or business data? Data passing through external SaaS systems carries risk.
  4. What's your monthly SaaS cost? If it's 50,000 THB/month, custom development pays for itself in 2–3 years.
  5. Is software part of your competitive advantage? If your software is part of your USP, custom is the answer.

When to Choose SaaS

  • Business is just starting and needs to validate the model first
  • Processes are standard with nothing special about them
  • Limited budget in the short term
  • Need to go live within 2–4 weeks
  • No internal resources to maintain a custom system

Hybrid Approach: Start with SaaS, Then Go Custom

Many businesses start with SaaS — Shopify for e-commerce, Xero for accounting — then as they scale, build a custom backend that connects to existing SaaS via API.

This is the pragmatic approach Adowbig recommends for growing SMEs.


How Adowbig Can Help

We develop custom software through a clear process:

  1. Discovery Workshop — Deeply understand your business processes and requirements
  2. Prototype & Validate — Build a prototype before committing to full development
  3. Agile Development — 2-week sprints with demos every sprint so clients see progress throughout
  4. QA & UAT — Testing with real users before go-live
  5. Post-launch Support — SLA and support team after delivery

Want advice on whether to choose custom or SaaS? Consult the Adowbig team for free — we give honest assessments with no hidden agenda.

Custom SoftwareSaaSSoftware DevelopmentSMEDigital Transformation