Digital income
SaaS Businesses
Software run as a service, billed monthly or annually to the people using it.
How the money actually reaches you
Customers subscribe and are billed on a recurring schedule through a payment processor or a merchant-of-record billing provider, which deducts fees and pays out on a rolling cycle. Business customers may instead be invoiced on net terms, which means the revenue is recognised before the cash arrives and sometimes long before. Every renewal is a re-decision by the customer, so the reported monthly figure is the net of new subscriptions, expansions, downgrades and cancellations. Unlike every other model in this section, the product must keep running: you are selling availability, and an outage is a refund conversation.
The customer, directly. A payment processor or a marketplace stands between you and the money and takes a fee for it; an app store or platform takes a commission set in its developer terms. What you actually sell may be a file, a licence, access, a physical parcel someone else ships, or the right to call an interface.
Fastest of the three. Card money typically settles to the processor within days and is paid out on a rolling schedule, minus a reserve on new or high-risk accounts. Marketplaces and app stores pay monthly, in arrears, after their own hold period.
Read the payer, the intermediary and the schedule before anything else. Who pays, who sits in the middle taking a share, and how long after the work the money arrives explain most of the difference between these fourteen businesses.
The structural facts
Six lines, in two halves. The first three are what the model takes — money up front, waiting time, and the rhythm of work it never stops needing. The last three are what happens once it earns: how the income fades if nothing new is added, what stops it growing past a point, and what, if anything, stops the next person copying it. A model with no answer to the last two can still pay; it just does not compound.
- Capital to start
- The highest here in practice: engineering time, infrastructure that costs money from day one, and a support function that appears the moment there are customers.
- Time to first dollar
- Months to build something a business will pay for, then a sales cycle on top. Business customers evaluate, trial, and involve procurement.
- Ongoing effort
- Continuous and operational. Uptime, security patches, support, onboarding and a roadmap. This is a company, not an asset.
- How it decays
- Operational rather than gradual: dependencies expire, certificates lapse, vulnerabilities are disclosed. An unattended service does not fade — it breaks, and then it churns.
- What caps it
- The number of businesses with the problem and the budget, plus your ability to support them. Software scales; support and security do not scale for free.
- What stops a copycat
- Switching cost. Data inside the product, integrations into a customer's workflow, trained staff and compliance approvals are what stop a customer leaving — not features, which are copied.
What it costs to run
- Cloud infrastructure, databases and backups
- Engineering and design
- Payment processing or merchant-of-record fees
- Support tooling and staff
- Security review, monitoring and, for larger customers, compliance audits
- Sales and marketing, which usually becomes the largest line
How it typically fails
- It is built for a problem nobody is budgeting to solve.
- Churn exceeds new business and the founder mistakes a retention problem for a marketing problem.
- A security incident ends the trust and the contracts at the same time.
- Infrastructure costs scale with usage while pricing does not.
- Support consumes all the engineering time and the product stops improving.
Does it sell?
Whether a business can be sold is the plainest test of whether it is an asset or a job. A buyer pays for income that continues without the person who built it, which means verifiable revenue, a customer relationship that transfers, and a distribution channel that does not walk out of the door with the founder. This section describes whether that market exists for this model — not what anything is worth, which no honest public source can give.
The most developed exit market in the section. Small services trade through online-business marketplaces and brokers; larger ones attract private equity and strategic buyers. Buyers underwrite recurring revenue quality, cohort retention, customer concentration, gross margin after infrastructure, and code and security diligence. Contracts that survive a change of control are worth more than month-to-month ones.
Where people look
A storefront for selling digital files, courses and memberships, handling checkout, file delivery and sales tax on the seller's behalf.
Fee is taken per sale rather than as a monthly subscription
Visit Gumroad ↗A publishing platform for email newsletters with paid subscriptions, payment processing and a subscriber list built in.
Takes a percentage of paid subscription revenue plus card processing
Visit Substack ↗Amazon's self-publishing service for ebooks and print-on-demand paperbacks, which pays the author a royalty on each sale.
Royalty rate depends on list price band and file delivery size
Visit Amazon Kindle Direct Publishing ↗Hosted software for building and selling online courses, including payments, student accounts and drip release of lessons.
Visit Teachable ↗Sponsored links are labelled. Listing a service is not an endorsement of it, and nothing on this page is advice.
Frequently asked
Is SaaS passive income?
What actually stops customers leaving?
Do I have to charge sales tax on software?
Others running on the same engine
Subscription Websites and Membership Sites
Gated content or a community that members pay for monthly or annually.
Paid Newsletters
Writing delivered to an inbox, paid for by subscribers, sponsors, or both.
Mobile Apps
Software distributed through app stores, paid for by users, subscriptions or advertising.
Online Courses
Recorded teaching sold once and delivered many times, direct or through a marketplace.
Digital Templates and Downloads
Files sold repeatedly — templates, presets, fonts, printables, plugins, spreadsheets.
Stock Photography Portfolios
Images, video clips and audio licensed repeatedly through agencies, paid per download.
E-Commerce With Outsourced Fulfilment
Selling physical goods someone else stores and ships — third-party logistics, print-on-demand, or dropshipping.
Domain-Name Portfolios
Holding registered domain names for lease, parking revenue or eventual resale.
Data and API Licensing
Selling access to a dataset or an interface, priced by seat, by call, or by contract.
Research only. This page describes how a business model works, what it costs and how it fails. It does not recommend starting one, does not estimate what anyone earns, and is not investment, tax or legal advice.