Sixty percent of the twenty most popular budgeting apps share your financial data with third parties, according to 2026 research from privacy firm Incogni. Most of them do it through Plaid, the aggregator that sits between your bank and the app on your phone, quietly storing your credentials and reselling anonymized transaction data. And 2025 was a record year for financial-services breaches in the United States, with 739 confirmed incidents — a number that kept climbing into 2026, when a single fintech lender disclosure exposed close to a million accounts in one event.
If that makes you want to move your money data off someone else's server, you have two serious open-source options: Firefly III and Actual Budget. Both are free, both are self-hosted, and both will run happily on a $5-a-month VPS or a Raspberry Pi under your desk. But they are not the same tool wearing different skins — they solve genuinely different problems, and picking the wrong one means fighting your software every month instead of using it.
Two Different Philosophies, Not Two Flavors of the Same App
The fastest way to understand the split: Actual Budget is a budgeting tool. Firefly III is an accounting system.
Actual is built around zero-based, envelope-style budgeting — the method popularized by YNAB (You Need A Budget). Every dollar you earn gets assigned a job the moment it arrives: rent, groceries, the annual car insurance payment you're saving toward. The entire interface is organized around one question — how much do I have left in this category right now? — and it answers that question fast, with a clean, opinionated UI that gets out of your way.
Firefly III takes a different starting point. It treats your finances the way a business treats its books: every transaction has a source account and a destination account, and every entry is recorded twice — once as money leaving one place, once as money arriving in another. That's double-entry bookkeeping, the same foundation used by professional accounting systems (and by plain-text ledgers like Beancount). Firefly III's interface reflects it: deep account hierarchies, piggy banks, bills, rules-based auto-categorization, and reporting that lets you slice your entire financial history by account, category, budget, or tag going back years.
Neither approach is "better" in the abstract. The mismatch happens when someone who wants "tell me if I can afford takeout this week" installs Firefly III and finds it overkill, or someone who wants "show me my complete net worth history across twelve accounts since 2019" installs Actual and finds it too simple.
Firefly III: A Full Accounting System You Host Yourself
Firefly III is a PHP application, typically deployed via Docker Compose alongside a database — MariaDB by default, though it's straightforward to swap in PostgreSQL by renaming the environment variables and adjusting the compose file. It needs a small set of PHP extensions (bcmath, curl, intl, mbstring, openssl, sodium, and a handful of others), all bundled into the official container image, so in practice "requirements" means "Docker and about 15 minutes."
What you get in exchange for that setup time:
- True double-entry bookkeeping. Every transaction is a transfer between two accounts, which makes reconciliation and historical reporting far more rigorous than a simple in/out ledger.
- Rules and auto-categorization. Define a rule once ("if description contains 'WHOLEFDS', category = Groceries") and Firefly III applies it to every future import.
- Deep reporting. Multi-year trend charts, budget-vs-actual, category breakdowns, and a REST API if you want to pull your data into something else.
- Bank sync via GoCardless (formerly Nordigen), which covers most European banks well but has thinner U.S. coverage — a real limitation if you're a North American user hoping for one-click sync with your checking account.
The learning curve is real. New users regularly get tripped up by the account-type model (asset vs. expense vs. revenue accounts aren't just labels — they determine how the double-entry math works) and by rule ordering when multiple rules could match the same transaction. Give yourself a weekend, not a lunch break, to get comfortable.
Actual Budget: Fast, Local-First, and Built for One Question
Actual ships as a single Docker container with no external database dependency at all — its entire state lives in a SQLite file inside the container's data volume. Pull the image, map a port, mount a volume, and you're running. It's meaningfully simpler to self-host than Firefly III, which matters if your goal is "get budgeting working tonight" rather than "build a personal accounting platform."
Actual is local-first by design: the app works offline and syncs quietly across devices when you reconnect, with optional end-to-end encryption for the sync layer. You get the envelope-budgeting method, a clean transaction register, and a built-in report builder that covers net worth and cash flow — solid, if intentionally less exhaustive than Firefly III's reporting.
For bank sync, Actual leans on GoCardless in Europe and SimpleFin (a paid service, roughly $15/year) in North America — worth noting, since "free and open source" doesn't always mean "free bank connections." Many self-hosters skip automated sync entirely and do a weekly CSV import instead, which both tools support, though migrating historical transactions into either app still means manually rebuilding your account names, category structure, and opening balances — expect an afternoon of cleanup no matter which tool you choose.
What Self-Hosting Actually Costs
"Free and open source" doesn't mean "free to run." You still need somewhere for the container to live. Realistic options:
- A Raspberry Pi you already own — effectively free, and plenty of power for either app's modest resource needs.
- A small VPS (DigitalOcean, Hetzner, Linode) running $4–$6/month — enough headroom for Firefly III plus its database, or Actual's single container.
- A home NAS (Synology, Unraid, TrueNAS) if you're already running one for media or backups — just add another Docker Compose stack.
Compare that to a YNAB subscription at roughly $109/year, or $14.99/month, and the math is straightforward: a $5 VPS running either tool pays for itself against YNAB in about six weeks, and every month after that is pure savings — before you even count the value of not handing your transaction history to a third party.
The one line-item worth budgeting for either way is bank sync. GoCardless requires a paid business account for new signups in 2026 (the free personal tier is gone), and Actual's North American SimpleFin connection runs about $15/year. Firefly III and Actual both work perfectly well with manual CSV imports if you'd rather skip that cost — you'll just be doing a weekly five-minute import instead of automatic sync.
A Quick-Start Checklist for Either Tool
Whichever you pick, the setup sequence looks the same:
- Provision the host. Confirm Docker and Docker Compose are installed on your VPS, Pi, or NAS.
- Pull the official compose file from the project's GitHub repo rather than hand-rolling your own — both projects maintain a tested
docker-compose.ymlthat saves you from chasing environment-variable typos. - Set a strong app key/secret before you enter any real financial data, and back it up somewhere outside the container (losing it can make your encrypted data unrecoverable).
- Start with one account. Resist the urge to import every account and five years of history on day one. Add your primary checking account, get comfortable with categorization for a week, then expand.
- Schedule backups. Firefly III's database and Actual's SQLite file are both single files (or a single database dump) you can cron-job to off-site storage — the whole point of self-hosting is that you, not a vendor, are responsible for durability.
- Decide on sync now, not later. Retrofitting bank sync onto months of manually entered transactions means reconciling duplicates by hand — pick your import strategy before you've built up a backlog.
Which One Should You Actually Install?
Ask yourself one question: do you want to control spending, or do you want to understand your entire financial position?
- Pick Actual Budget if you're a freelancer or solo developer who wants a fast, YNAB-style envelope system to stop overspending on discretionary categories — dining out, subscriptions, the annual conference travel budget — and you'd rather spend five minutes a week in the app than fifty.
- Pick Firefly III if you're running multiple accounts (business checking, personal savings, a couple of credit cards, maybe a crypto wallet) and you want one system that reconciles all of it with real double-entry rigor, rules-based automation, and years of historical reporting you can query later.
Plenty of technical users end up running both, or start with Actual and graduate to Firefly III once their finances get more accounts to track. That's a legitimate path — just don't expect to migrate cleanly between them; treat the switch as a fresh start with a manual opening-balance entry, not a data export/import.
The Business Case: Why Self-Hosting Your Books Isn't Just a Privacy Hobby
If you're a freelancer or run a small business alongside your personal finances, the privacy argument for self-hosting extends directly into your bookkeeping. The same reasoning that makes you uneasy about a budgeting app reselling your grocery habits applies double to your business's revenue, client payments, and vendor contracts — that's data you're often contractually or legally obligated to protect, not just data you'd prefer stayed private.
It's also worth separating "budgeting" from "bookkeeping" here, because business owners frequently need both and conflate them. A budgeting app like Actual answers "how much can I spend this month?" A bookkeeping system needs to answer harder questions your accountant will ask at tax time: which client payments are still outstanding, what your true profit margin looks like after expenses, and whether a given transaction is deductible. Firefly III's double-entry model gets you closer to that second job than Actual does, but neither tool was built specifically for small-business accounting — they're personal finance apps that happen to scale up reasonably well.
Keep Your Books as Open and Portable as Your Budgeting App
If double-entry bookkeeping and data ownership are what drew you to Firefly III in the first place, it's worth knowing there's an entire category of tools built on the same principle for business accounting specifically: plain-text, version-controlled ledgers. Beancount.io takes that idea all the way — your books live in a human-readable text format you fully own, with the same double-entry discipline, but built for tracking a business rather than a household budget. Explore the documentation to see how it compares, or get started for free if you want your business's financial records to be as transparent and portable as the self-hosted tools in this guide.