Software-as-a-service (SaaS) is a cloud computing model where a third-party provider hosts applications and delivers them to users over the internet, typically through a web browser. You don’t install anything locally; you log in and the software runs on someone else’s servers. This model now dominates B2B software. Below, we’ll cover how SaaS works technically, compare it to other cloud models, walk through pricing structures, and explain what to look for when evaluating vendors.
What is software-as-a-service?
Software-as-a-service (SaaS) is a cloud computing model where a third-party provider hosts applications and delivers them to users over the internet, typically through a web browser. Rather than installing software on your computer or company servers, you log in through a browser and the application runs on the vendor’s infrastructure. Think of it this way: with traditional software, you buy a license, install the program, and manage everything yourself. With SaaS, the vendor handles hosting, maintenance, security patches, and upgrades while you pay a recurring subscription fee. Cloud computing, in plain terms, means using someone else’s computers over the internet. The “cloud” is just a network of servers in data centers that store and process your data remotely.
Key characteristics of SaaS
SaaS products share a few technical and commercial traits that set them apart from other software delivery models.
Cloud hosting and browser access
Applications run on remote servers managed by the vendor. You access them through a web browser or mobile app without downloading anything to your device. This means you can work from any computer with an internet connection.
Subscription pricing
Users pay recurring fees, usually monthly or annually, rather than one-time license purchases. Common pricing structures include per-seat (you pay for each user) and usage-based (you pay for what you consume).
Multi-tenant architecture
A single instance of the software serves multiple customers simultaneously. Your data stays isolated and secure from other customers, but everyone shares the same underlying infrastructure. This efficiency is what allows SaaS vendors to offer lower prices than traditional software.
Vendor-managed updates
The provider handles all maintenance, security patches, and feature releases. You always run the current version without lifting a finger. No more waiting for IT to schedule an upgrade window.
Elastic scalability
You can add or remove users and capacity without purchasing new hardware. If your team grows from 10 to 100 people, you adjust your subscription. If you need more storage or processing power, the vendor scales the infrastructure.
How SaaS works
The technical flow is straightforward once you see it step by step. When you log in to a SaaS application, your browser sends a request to the vendor’s servers. Those servers verify your credentials, process your request, and send back the interface you see on screen. Any data you create or modify gets stored in the vendor’s database, not on your local machine. Here’s what happens behind the scenes:
- User authentication: Your login credentials are verified by the provider’s identity system
- Application layer: The software logic runs on vendor-managed servers in a data center
- Data storage: Your information lives in the provider’s cloud database
- Delivery: The interface and results render in your browser
This architecture explains why you can start a document on your laptop, continue on your phone, and finish on a tablet. The data lives in the cloud, not on any single device.
Advantages of SaaS
Lower upfront costs
No large capital expenditure for licenses or hardware. The subscription model spreads costs over time, which helps with cash flow and budgeting. A startup can access enterprise-grade software without a six-figure check.
Faster time to value
Deployments take days or weeks rather than months. There’s no infrastructure to provision, no installation to schedule, no compatibility testing. You sign up, configure your settings, and start working.
Automatic updates
The vendor pushes updates to all customers simultaneously. Your IT team doesn’t spend weekends patching servers. You get new features and security fixes without disruption.
Anywhere access
Users can work from any location with internet connectivity. This supports remote teams, distributed offices, and the reality that work happens outside the building.
Disadvantages of SaaS
Data security and compliance risk
Your data resides on third-party servers. You’ll want to verify the vendor’s security practices and regulatory compliance. Look for SOC 2 reports, and confirm certifications relevant to your industry (GDPR for European data, HIPAA for healthcare).
Limited customization
SaaS products offer configuration options, but rarely allow the deep code-level modifications possible with on-premise software. If your workflow is unusual, you may find yourself adapting to the tool rather than the other way around.
Vendor lock-in
Switching providers can be difficult. Data migration is complex, and your team has built workflows around specific features. Before signing a contract, evaluate data export options and what happens if you decide to leave.
Ongoing subscription costs
Over a long enough timeline, subscription fees may exceed what you would have paid for a perpetual license. For mature, stable use cases with minimal need for updates, the math sometimes favors on-premise.
SaaS business model and pricing
Per-seat pricing
You pay based on the number of users. This model is predictable but can become expensive as teams grow. Slack uses this approach.
Usage-based pricing
You pay based on consumption metrics like API calls, storage, or transactions. Cost aligns with value received, but bills can be unpredictable. Twilio charges this way.
Tiered pricing
Multiple feature packages at different price points. Small businesses start on a basic tier; enterprises pay more for advanced capabilities. HubSpot structures pricing this way.
Freemium
A free tier with limited features; paid tiers unlock more. This model supports product-led growth, where users try before they buy. Dropbox popularized this approach.
Examples of SaaS companies and products
Salesforce for CRM
The original enterprise SaaS company. Salesforce manages sales pipelines, customer data, and forecasting. It went public in 2004 and proved the subscription model could work at scale.
HubSpot for marketing automation
Combines CRM, email marketing, content management, and analytics in one platform. Popular with growth-stage B2B companies building their first marketing stack.
Slack for team communication
Real-time messaging and collaboration. Integrates with hundreds of other SaaS tools via APIs, which makes it a hub for daily work.
Zoom for video conferencing
Video meetings, webinars, and virtual events delivered through browser and app. Usage grew rapidly during 2020 as remote work became standard.
How to evaluate a SaaS product
1) Define the business problem
Start with the workflow or pain point you’re trying to solve. Avoid feature-shopping without clear requirements. The best tool is the one that fits your actual situation.
2) Assess security and compliance
Request SOC 2 reports. Review data residency options. Confirm certifications relevant to your industry.
3) Review pricing and total cost of ownership
Model costs at current and projected usage levels. Account for implementation, training, and integration expenses.
4) Test integrations and API access
Verify the product connects with your existing tech stack. If it doesn’t talk to your CRM or marketing automation platform, you’ll create data silos.
5) Validate vendor viability
Research funding, customer base, and product roadmap. Consider what happens if the vendor is acquired or shuts down.
Frequently Asked Questions about Software-as-a-Service
Netflix is not a SaaS company. It delivers entertainment content rather than business software applications. The technical delivery model is similar (streaming over the internet), but the product category is different.
Salesforce, Microsoft (for its cloud productivity suite), Adobe, and ServiceNow each generate billions in annual recurring revenue.
AI is being integrated into SaaS products rather than replacing them. Salesforce Einstein and HubSpot’s AI assistants add automation and prediction to existing platforms. The delivery model remains SaaS.
Customers typically retain ownership of their data per the vendor’s terms of service. However, you’ll want to verify data export options and portability before signing contracts.
