What is the difference between agile and waterfall methodology in software development?

Oscar Bout · 21 Sep 2026

The difference between the agile method and the waterfall method lies in the way you structure a software project. With waterfall, you work step by step through fixed phases, where each phase must be fully completed before you start the next. With agile, you work in short cycles and continuously refine the product based on feedback. Which method best suits your project depends on how clearly defined your requirements are and how much room you want for adjustments along the way. In this article, we answer the most frequently asked questions about both methods.

When do you choose agile and when do you choose waterfall?

You choose agile when the requirements of your project are not yet fully defined or when you expect them to change during the project. You choose waterfall when the scope, budget, and delivery date are clear from the outset and there is little room for interim adjustments.

A few practical rules of thumb help you make this choice:

Choose agile if you want to see a working product quickly, want to make regular adjustments, and want to collaborate closely with the development team.
Choose waterfall if you are working with strict regulations, fixed contracts, or when the client has limited availability for interim consultations.
Choose agile for innovative products such as apps, platforms, or AI applications where market feedback determines the direction.
Choose waterfall for projects with a clearly defined end result, such as migrating an existing system to a new environment.

In practice, many teams today opt for a hybrid approach: the broad outlines are planned according to waterfall, while the execution follows agile.

What are the main advantages and disadvantages of the agile method?

The agile method offers a great deal of flexibility and ensures that you see visible results quickly. The biggest advantage is that you can adjust course during the project based on new insights or changing needs. The downside is that agile requires active involvement from all stakeholders and is less predictable in terms of final costs and delivery date.

Advantages of agile

Rapid delivery of working software in small increments
Flexibility to shift priorities
Regular feedback ensures a product that aligns with the actual need
Problems are identified and resolved early

Disadvantages of agile

More difficult to guarantee an exact price and date upfront
Requires regular availability from the client
Without proper guidance, scope can grow quickly (also known as “scope creep”)
Less suitable when documentation is a hard requirement

What are the main advantages and disadvantages of the waterfall method?

The waterfall method provides structure and predictability. You know in advance what will be built, when it will be ready, and what it will cost. The downside is that there is little room for mid-project adjustments. If a requirement changes halfway through, it takes a great deal of time and money to reverse that.

Advantages of waterfall

Clear planning with fixed milestones
Works well with fixed budgets and contracts
Comprehensive documentation of the entire system
Less dependent on continuous involvement from the client

Disadvantages of waterfall

Little flexibility when requirements change
The final product is tested late, meaning errors are discovered late
Risk that the delivered product no longer matches the current need
Less suitable for innovative or rapidly changing markets

Which method works better for custom software?

For custom software, the agile method works better in most cases. With custom development, the exact shape of the product is rarely fully clear from the start. Agile allows you to discover step by step what the product needs to do, while delivering working components early on.

In custom software development, requirements are often dependent on user feedback, technical possibilities, and business priorities that shift during the project. Waterfall works less well in that case, because you lock in all decisions at the beginning that may no longer be correct later on.

Agile also fits better with the reality of custom development: you are building something that does not yet exist, and that calls for an iterative process of learning and adapting. This also makes it a popular choice in fintech, AI applications, and mobile app development.

How does an agile sprint work in practice?

An agile sprint is a fixed working period, usually one to four weeks, during which the team builds and delivers an agreed set of features. At the start of the sprint, you collectively decide which tasks will be picked up. At the end, the team presents the results and you, as the client, provide feedback.

A typical sprint looks like this:

Sprint planning: The team and the client determine together which tasks fit within the sprint.
Daily stand-up: A brief check of no more than 15 minutes where the team discusses what has been done, what is on the schedule for today, and whether there are any blockers.
Development: The team works on the agreed tasks and resolves bottlenecks.
Sprint review: The delivered work is demonstrated to the client for feedback.
Retrospective: The team discusses internally what can be improved in the next sprint.

This rhythm ensures that as a client you see what has been built every sprint and can immediately steer priorities for the next round.

Can a remote development team work agile?

Yes, a remote development team can work agile perfectly well. Agile is based on communication, short feedback cycles, and collaboration, and that works well remotely too, provided the right tools and working agreements are in place. It does require clear lines of communication and a well-structured collaboration.

Practical prerequisites for agile remote collaboration:

Use of project management tools such as Jira, Linear, or Trello for transparency on tasks and progress
Fixed moments for daily stand-ups and sprint reviews via video call
Clear agreements on availability and response times
A local point of contact or technical supervisor who acts as a bridge between you and the remote team

That last point makes a big difference. When there is someone who speaks the language, understands the culture, and is technically knowledgeable, collaboration with a remote team runs just as smoothly as with a team around the corner.

How 3Bird helps with agile software development at a distance

At 3Bird, we combine the flexibility of agile working with the structure you need as a client. Our team of experienced developers in Nepal works together with Dutch fractional CTOs who guide your project in your own language. This way, you benefit from the advantages of an international team without sacrificing communication or quality.

What we concretely offer:

Experienced remote developers who work in agile sprints, fully transparent and results-driven
Dutch fractional CTOs as your fixed point of contact for technical direction and progress
Flexible scaling of your team up or down based on the phase of your project
Support for a wide range of technologies, from React and Flutter to Java, .NET, and AWS
Rates from €25 to €30 per hour, significantly more affordable than local alternatives

Whether you choose agile, waterfall, or a combination of both, we are happy to think along with you about the approach that best suits your project. Get in touch via contact@3bird.nl or call us at +(31)75-7993038 and discover how we can be your software development partner.