To-Do List Apps With Strong Privacy: What to Look For

A to-do list app seems like an unlikely source of privacy concern. It’s just tasks, after all. But these apps often hold a surprising amount of personal information: work deadlines, financial errands, medical appointments, even passwords or notes you’ve jotted down. If that data leaks or gets sold to advertisers, it can be more than an annoyance. It can compromise your security.

Wirecutter’s latest roundup of the best to-do list apps for 2026 focuses on features, usability, and reliability. That’s helpful, but it leaves out a growing concern: how well does each app protect your data? I’ve looked at the three apps they recommend—Things 3, Todoist, and Microsoft To Do—through a privacy lens. Here’s what I found and what you can do to lock down your lists.

Why It Matters

Data breaches are no longer rare events. In 2025 alone, several popular productivity apps reported unauthorized access to user accounts or exposed task data due to weak third-party integrations. To-do list apps typically sync across devices, which means your data lives on company servers. How that data is encrypted, who can access it, and what those companies do with it varies widely.

Most users never check the privacy settings of a to‑do app. They assume a trusted name like Microsoft or Todoist handles security well. That’s not always wrong, but the devil is in the details: does the app use end‑to‑end encryption? Can employees read your tasks? Does it share data with analytics firms? The answers are not the same for every app.

What Happened

Wirecutter published its annual review of to‑do list apps in December 2025. They tested over a dozen apps and selected three based on ease of use, cross‑platform support, and reliability. Their top picks are Things 3 (for Apple users), Todoist (for cross‑platform and advanced project management), and Microsoft To Do (for tight integration with Office 365). Each has strengths, but none offer perfect privacy out of the box.

Privacy Trade‑Offs by App

Things 3 (macOS/iOS only) stores your tasks locally on your device. That’s a strong privacy feature: your data never touches a server unless you use its optional cloud sync via Things Cloud. However, Things Cloud has not undergone a public third‑party audit, and the company’s privacy policy states that encrypted data is stored on servers in Germany. According to Cultured Code, the developer, they cannot read your tasks because encryption keys are derived from your account password. That’s a good design, but the lack of an independent verification means we have to take their word for it.

Todoist uses server‑side encryption, meaning your tasks are encrypted when stored on their servers (at rest) and while in transit (TLS). But Todoist employees have access to your data for support or feature improvement. The company’s privacy policy states they do not sell your data to third parties, but they do share aggregated, anonymized data with analytics partners. If you use Todoist’s smart scheduling or AI features, extra data is processed. For most everyday users, this trade‑off is acceptable. For someone managing highly sensitive work projects, it may not be.

Microsoft To Do operates under the same privacy framework as the rest of Microsoft 365. Your data is encrypted at rest and in transit, and Microsoft promises not to use your tasks for advertising. However, the company does collect usage data to improve features. Like Todoist, Microsoft employees can technically access your data in limited circumstances (such as troubleshooting with your consent). Microsoft’s enterprise customers can get additional data protection guarantees through their IT administrators, but ordinary consumers cannot.

What You Can Do

You don’t need to abandon a good to‑do app to protect your privacy. A few adjustments make a big difference.

First, check whether your app supports two‑factor authentication (2FA). All three apps here offer it. Enable it for your account—this is the single most effective step against unauthorized access, even if the app’s server is compromised.

Second, review the app’s sharing and integration permissions. Many tasks get exposed because a user connected a third‑party service (like Zapier or Slack) without checking what data that service can see. Only connect what you absolutely need, and periodically audit those connections.

Third, if you use a cross‑platform app like Todoist or Microsoft To Do, consider turning off any “smart” features that require sending task content to AI or suggestion engines. These are often enabled by default.

Fourth, for the most sensitive data, consider using a dedicated encrypted notes app rather than storing it inside a to‑do task. Apps like Standard Notes or Cryptee are designed for end‑to‑end encryption.

Finally, read the privacy policy. It’s tedious, but it’s the only reliable way to know what the company does with your data. Look for sections on data sharing, encryption, and whether they comply with GDPR or CCPA. If a policy is vague or grants itself broad data‑use permissions, that’s a red flag.

The Bottom Line

None of the three top‑rated to‑do list apps are privacy disasters, but none are fully private either. Things 3 comes closest for Apple users who don’t need cloud sync across non‑Apple devices. Todoist and Microsoft To Do are solid for daily use as long as you’re aware of their data handling and take basic precautions. The goal is not perfection—it’s informed use.

Sources

  • Wirecutter, “The 3 Best To-Do List Apps of 2026,” December 2025.
  • Cultured Code (Things 3) privacy policy, accessed April 2026.
  • Todoist privacy policy, April 2026.
  • Microsoft Privacy Statement, April 2026.
  • GDPR and CCPA compliance documentation for each service.