5 Most Secure Cloud Storage Providers: Free & Premium Services Tested
Security and privacy are two of the greatest concerns for cloud storage users, but you don't need to be an expert in encryption to find the most secure cloud storage. We’ve done the heavy lifting for you, so read on.
Written by Aleksandar Kochovski (Writer)
Reviewed by Valentina Bravo (Editor)
Facts checked by Igor Kurtz (Fact-checking editor)
Last Updated:
All our content is written fully by humans; we do not publish AI writing. Learn more here.
Key Takeaways: These Are the Most Secure Cloud Storage Services for 2025
- Sync.com — The best secure and affordable cloud storage, offering whole-storage encryption with Microsoft Office integration.
- pCloud — A Swiss-based cloud storage with an encrypted folder, lightning-fast speeds, stunning design and entertainment features.
- Icedrive — Sleek, speedy cloud storage with flexible sync options, a secure folder with encryption, and affordable lifetime plans.
- Internxt — A future-proof cloud storage with quantum-resistant encryption and open-source apps.
- MEGA — A cloud storage solution with generous free storage with secure communication tools.
Facts & Expert Analysis About Secure Cloud Services:
- Client-side encryption: Client-side encryption (also called zero-knowledge or end-to-end encryption) prevents cloud providers from accessing your data, as files are encrypted before leaving your device, and clients hold the encryption keys.
- Encryption standards: Most cloud storage services offer AES-256 encryption at rest and TLS/SSL in transit to encrypt your files. Although this encryption is impossible for humans to hack, quantum computers could theoretically crack the encryption in minutes, leading to some security providers, like Internxt, offering quantum-resistant encryption.
- Data protection laws: Data privacy laws determine how companies handle user data. The gold standard for online privacy laws is the European Union’s GDPR, which applies to both EU citizens and customers of companies incorporated in the EU.
Cloud storage has become an essential digital utility, but not all services offer the same level of protection for your files. This article will reveal the five most secure cloud storage services and how they work.
A truly secure cloud storage system should employ zero-knowledge encryption, also known as client-side or end-to-end encryption (though these are not fully synonymous terms). Plus, a strong privacy policy and adherence to privacy laws like the GDPR are must-haves.
The services we’ve selected feature on our list of the best cloud storage and fulfill these criteria. Some focus on robust free cloud storage, while others offer a full feature package. Others put all of their eggs in the security basket, with a minimal feature set. No matter what your needs are, we have you covered.
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05/09/2022 Facts checked
Added Internxt as an honorable mention, included key takeaways.
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06/25/2022 Facts checked
Updated Sync.com’s plans and pricing information.
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05/24/2023 Facts checked
Updated information about Icedrive’s future plans and data centers
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12/08/2023 Facts checked
We updated MEGA’s price offerings.
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08/31/2024 Facts checked
Added video reviews for cloud storage providers in the list.
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01/25/2025 Facts checked
Added new video ranking the most secure cloud storage providers.
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02/11/2025 Facts checked
This article was updated with more details about Sync.com’s security and features, as well as a few details pertaining to pCloud, Icedrive and MEGA’s security.
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03/11/2025 Facts checked
We updated this article’s information about Internxt’s plans and features.
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04/04/2025 Facts checked
This article was rewritten following a reassessment of the cloud security capabilities of the services we reviewed.
What Is the Most Secure Cloud Storage? Cloudwards’ Choice: Sync.com
Cloudwards’ Choice: Sync.com
Sync.com is my personal favorite cloud storage, and it just so happens to be the most secure as well. Client-side encryption applies to all of your files, which are stored on Canadian servers. In addition, it integrates with Microsoft Office, which is a unique achievement for an end-to-end-encrypted cloud storage service.
The 5 Most Secure Cloud Storage Services
| Cloud: | Free Storage | Best Price | Server Locations | End-to-End Encryption | Online Collaboration | Advanced Sharing | Security |
|---|---|---|---|---|---|---|---|
 | 5GB | $4.80 per month (one-year plan), 2TB | Canada | Microsoft Office | AES-256, TLS/SSL | ||
 | 10GB | $8.33 per month (one-year plan), 2TB | EU, U.S. | * | None | AES-256, TLS/SSL | |
 | 10GB | $4.99 per month (two-year plan)1TB | EU, U.S. | * | None | Twofish, TLS/SSL | |
 | 1GB | $4.40 per month (one-year plan), 3TB | EU | None | AES-256, TLS/SSL | ||
 | 20GB | $8.76 per month (one-year plan), 2TB | EU, Japan, Canada, New Zealand | None | AES-256, TLS/SSL |
1. Sync.com — Best Cloud Storage With Zero-Knowledge Encryption
Sync.com is a security powerhouse, offering client-side encryption for all of your storage. Unusual for such a secure service, it integrates with Microsoft Office and provides robust and secure file sharing, letting you easily collaborate within an encrypted environment. Plus, it’s one of the cheapest cloud storage services and even offers unlimited cloud storage.
Sync.com Hands-On Testing
Overall, we found Sync.com’s apps to be well designed and easy to use. Sync.com installs a sync folder on your device, and everything you copy to it is uploaded to the cloud. You can also designate files as online-only to save hard drive space. Its mobile apps are minimal yet capable, with the only notable feature being automatic uploads for photos.
Notes From the Lab: Sync.com Speed Test Results
In our cloud storage speed tests, we upload and download a 5GB folder of various files using a virtual machine in Dublin, Ireland, on a 1 Gbps connection, throttled to 100Mbps.
| First Try | Second Try | Average Time |
|---|---|---|---|
| Upload | 0:10:20 | 0:09:47 | 0:10:04 |
| Download | 0:15:17 | 0:14:55 | 0:15:06 |
Notes From the Lab: Sync.com Security Analysis
| Feature: | Encryption Protocols |
|---|---|
| Client-side encryption | Yes, entire storage |
| Encryption at rest | AES-256 |
| Encryption in transit | TLS/SSL |
| Jurisdiction | Canada |
| Applicable privacy laws | PIPEDA |
Key Privacy & Security Features:
- Client-side encryption
- Multi-factor authentication
- Collaboration in zero-knowledge environment
- Duplicate files across servers for data-loss protection
- Canadian privacy laws (PIPEDA)
- GDPR compliance (EU users)
- HIPAA compliance possible
Sync.com is incorporated in Canada, which has strong privacy laws. It complies with HIPAA as well, meaning it’s deemed safe enough to store sensitive medical data.
It also implements redundancy measures, so if one server suffers a critical failure, your files will still be recoverable. This is in addition to end-to-end encryption and login protections like two-factor authentication and single sign-on.
Sync.com Pricing & Value
Sync.com offers 5GB of free storage space. You can upgrade to a 2TB plan for just $4.80 per month on a yearly subscription, which is affordable compared to most other providers. You can also get unlimited cloud storage with a team account for relatively cheap. Read our full Sync.com review for more details.
- 5GB
- 2TB
More plans
- 6TB
- Price includes 3 users
- 1TB
- Monthly price for 1 user (3 users minimum) Yearly price for 3 users
- Unlimited GB
- Minimum 100 users, custom requirements, account manager, training options
2. pCloud — Best Secure Cloud Storage With Online Backup
pCloud is a Swiss-based company that offers one of the most capable and polished cloud storage services, with a wealth of entertainment-focused features such as a fully featured music player and Kodi integration. It also has a backup feature, letting you archive files in the cloud.
pCloud Hands-On Testing
pCloud has some of the best cloud storage apps out there, covering all major operating systems. Its desktop apps sync your files instantly with barely any delay, and its mobile apps sport some of the most user-friendly design we’ve seen in our years of testing. It is also among the fastest cloud services that we’ve tested.
Notes From the Lab: pCloud Speed Test Results
In our cloud storage speed tests, we upload and download a 5GB folder of various files using a virtual machine in Dublin, Ireland, on a 1 Gbps connection, throttled to 100Mbps.
| First Try | Second Try | Average Time |
|---|---|---|---|
| Upload | 0:07:02 | 0:07:10 | 0:07:06 |
| Download | 0:06:50 | 0:06:53 | 0:06:52 |
Notes From the Lab: pCloud Security Analysis
| Feature: | Encryption Protocols |
|---|---|
| Client-side encryption | Yes (paid add-on), single folder |
| Encryption at rest | AES-256 |
| Encryption in transit | TLS/SSL |
| Jurisdiction | Switzerland, EU, U.S. |
| Applicable privacy laws | DPA, GDPR (EU servers only) |
Key Privacy & Security Features:
- Client-side encryption (single folder, not free)
- Two-factor authentication
- Additional password protection for Crypto files
- Swiss privacy laws
- GDPR compliance (EU users)
Based in Switzerland, pCloud has to comply with the strictest data privacy laws in the world, namely the EU’s GDPR and Switzerland’s own DPA. Client-side encryption comes in the form of the pCloud Crypto add-on, though this is regrettably a paid feature. It also covers only one folder in your storage with additional password protection.
pCloud Pricing & Value
pCloud offers up to 10GB of free storage, contingent on completing a few tasks and referring friends to the service. Its paid plans are affordable, with the 2TB plan costing $8.33 per month on a yearly commitment. The true highlight is its lifetime cloud storage plans, which offer even more value for a one-time payment. Read our full pCloud review for more.
- 10GB
- 500GB
- 2TB
More plans
- + FREE Encryption
- 2TB
- + FREE Encryption
- 10TB
- Price per user (minimum 3)
- 1TB
- Price per user (minimum 3)
- 2TB
- Encryption for pCloud Drive
3. Icedrive — Fast, Secure Cloud Storage With Lifetime Plans
![Video thumbnail for the video: Ultimate Icedrive Review [2024 Pros and Cons Revealed]](https://img.youtube.com/vi/iVGsDxYVV-Y/maxresdefault.jpg)
Icedrive is one of our favorite secure cloud storage providers. It’s affordable, fast and well designed. It offers a more stripped-back experience, but it brings a much higher level of execution and more choices when it comes to syncing your files. It’s also affordable, nabbing a spot on our list of the cheapest cloud storage services.
Icedrive Hands-On Testing
Icedrive gives you the choice of using a standard sync folder, syncing existing folders or installing a virtual drive, similar to that of pCloud. All of its apps sport a clean and minimalistic design that makes the service easy to use, even for beginners.
Notes From the Lab: Icedrive Speed Test Results
In our cloud storage speed tests, we upload and download a 5GB folder of various files using a virtual machine in Dublin, Ireland, on a 1 Gbps connection, throttled to 100Mbps.
| First Try | Second Try | Average Time |
|---|---|---|---|
| Upload | 0:07:12 | 0:07:06 | 0:07:09 |
| Download | 0:07:11 | 0:07:41 | 0:07:26 |
Notes From the Lab: Icedrive Security Analysis
| Feature: | Encryption Protocols |
|---|---|
| Client-side encryption | Yes (not on free accounts), single folder |
| Encryption at rest | Twofish 256-bit |
| Encryption in transit | TLS/SSL |
| Jurisdiction | U.K., EU, U.S. |
| Applicable privacy laws | GDPR (EU servers only) |
Key Privacy & Security Features:
- Client-side encryption (single folder, not free)
- Two-factor authentication
- GDPR compliance (EU users)
- Less common Twofish encryption
Icedrive’s servers are located in the EU, which means you get GPDR protection for your sensitive data. It also uses Twofish encryption instead of the standard AES, which fewer people are familiar with — potentially making it less likely to be cracked. End-to-end encryption is available for all paying users, though like pCloud, it covers only one folder.
Icedrive Pricing & Value
Icedrive offers 10GB of secure storage for free users. Upgrading to a 3TB plan will cost you $8.99 per month on a two-year plan, and you can get a lifetime plan for better savings. Read our full Icedrive review for more.
- Bandwidth limit: 50GB
- 10GB
- Bandwidth limit: 250GB
- 100GB
- Bandwidth limit: 2TB
- 1TB
More plans
- Bandwidth limit: 8TB
- 3TB
- 512GB
- 2TB
- 10TB
- Additional 128GB storage for users who purchased the Lifetime Plan
- 128GB
- Additional 512GB storage for users who purchased the Lifetime Plan
- 512GB
- Additional 2TB storage for users who purchased the Lifetime Plan
- 2TB
4. Internxt — Most Innovative Encrypted Cloud Storage
Internxt offers the most comprehensive security suite of the services on this list. As an overall cloud storage system, it’s pretty sparse, offering little beyond the basics. Like pCloud, it has a cloud backup feature and also Internxt Send for secure file sharing. It also offers more security features, including a limited VPN and antivirus.
Internxt Hands-On Testing
Internxt’s apps aren’t the most impressive — the desktop app is a bit fiddly and the mobile apps lack automatic photo upload functionality. It uses the standard sync folder model, but there is no option to sync other folders. However, you can set files as online-only to save some space on your hard drive.
achievement given its dearth of features.
Notes From the Lab: Internxt Speed Test Results
In our cloud storage speed tests, we upload and download a 5GB folder of various files using a virtual machine in Dublin, Ireland, on a 1 Gbps connection, throttled to 100Mbps.
| First Try | Second Try | Average Time |
|---|---|---|---|
| Upload | 0:07:57 | 0:08:05 | 0:08:01 |
| Download | 0:09:26 | 0:09:30 | 0:09:28 |
Notes From the Lab: Internxt Privacy & Security Analysis
cybersecurity company Securitum.
| Feature: | Encryption Protocols |
|---|---|
| Client-side encryption | Yes, whole storage |
| Encryption at rest | AES-256 |
| Encryption in transit | TLS/SSL |
| Jurisdiction | EU |
| Applicable privacy laws | GDPR |
Key Privacy & Security Features:
- Two-factor authentication
- Client-side encryption
- Post-quantum encryption
- Open-source software
- Data duplication for redundancy
Data security is Internxt’s strong suit. In addition to offering client-side encryption for your private files, Internxt uses quantum-resistant cryptography to future-proof them against attacks from quantum computers. The software is open source, so anyone can audit its apps for bugs or malicious code. Cybersecurity firm Securitum audited Internxt in 2024.
Internxt Pricing & Value
Internxt is one of the cheapest cloud storage on this list, with 3TB of storage costing just $4.40 per month on a yearly plan. Like pCloud, it offers lifetime plans that offer even more value. Unfortunately, its free plan comes with only 1GB of storage. Read our Internxt review for more.
- 1GB
- Storage + VPN (FR), Antivirus, Backup & More
- 1TB
- Storage + VPN (FR, DE, PL), Antivirus, Backup & More
- 3TB
More plans
- Storage + VPN (FR, DE, PL, CA, UK), Antivirus, Backup & More
- 5TB
- Storage + VPN (FR, DE, PL), Antivirus, Backup & More
- 1TB
- Storage + VPN (FR, DE, PL, CA, UK), Antivirus, Backup & More
- 2TB
5. MEGA — Largest Secure Free Cloud Storage
MEGA is known for good security and its large free plan. It’s a reliable service that offers a standard feature set, with the somewhat unusual inclusion of an encrypted chat client. Its paid plans are similarly spacious, with enterprise plan users getting up to 10PB (that’s 10,000TB) of data.
MEGA Hands-On Testing
In terms of platform compatibility, MEGA supports all major operating systems. On desktop, it doesn’t use a separate folder for file syncing, letting you set up your own sync folders. The mobile app can automatically upload your photos, but during testing, we needed to open the app when the Android system put it to sleep so uploads could continue.
Notes From the Lab: MEGA Speed Test Results
In our cloud storage speed tests, we upload and download a 5GB folder of various files using a virtual machine in Dublin, Ireland, on a 1 Gbps connection, throttled to 100Mbps.
| First Try | Second Try | Average Time |
|---|---|---|---|
| Upload | 0:07:16 | 0:07:24 | 0:07:20 |
| Download | 0:08:14 | 0:08:02 | 0:08:08 |
Notes From the Lab: MEGA Security Analysis
| Feature: | Encryption Protocols |
|---|---|
| Client-side encryption | Yes, whole storage |
| Encryption at rest | AES-256 |
| Encryption in transit | TLS/SSL |
| Jurisdiction | EU, Canada, New Zealand, Japan |
| Applicable privacy laws | GDPR (EU), PIPEDA (Canada), Privacy Act (NZ) |
Key Privacy & Security Features:
- Client-side encryption
- Two-factor authentication
- End-to-end encrypted text and video chat
- Encrypted sharing links
- GDPR compliance (extends to all users)
- Open-source apps
- Password manager (paid users only)
MEGA is incorporated in New Zealand, but it operates servers in the EU, Canada and Japan as well, meaning it has to comply with the laws of all of those countries — including, importantly, the GDPR. Its end-to-end encryption applies to all files and is extended to free users as well. Like Internxt, MEGA also makes its apps open source.
MEGA Pricing & Value
MEGA is more expensive than the other services on this list, especially for its higher-capacity plans. That said, its smaller plans come at reasonable prices, with its 2TB plan costing $8.76 per month with a yearly commitment. Read our full MEGA review for more.
- 20GB
- File transfer: 2TB (Monthly plan) 24TB (yearly plan)
- 2TB
- File transfer: (monthly plan) 96TB (yearly plan)
- 8TB
More plans
- File transfer: 16TB (monthly plan) 192TB (yearly plan)
- 16TB
- Price per user (minimum 3) 3TB Transfer quota
- 100TB
Honorable Mentions
These two services didn’t quite make our top five, but they’re still worth taking a look at.
IDrive
IDrive is a service provider that straddles the line between online backup and cloud storage, though it clearly focuses on the backup aspect. It offers what is likely the most comprehensive suite of backup features, though its cloud storage features are basic. The good news is that you can enable client-side encryption for all of your sensitive files.
IDrive is also very cheap. A 5TB plan costs just $6.22 per month on a two-year plan. As a bonus, your storage is essentially doubled, as you get a separate 5TB of storage for your cloud sync space (this doubling applies to all plans). There’s no free plan, though. Read our full IDrive review for more.
- No credit card required.
- 10GB
- One user.
- 100GB
- One user, multiple computers. Plans starting from 5TB up to 100TB. Big discount for first-time signup.
- 5TB
More plans
- 5 computers, 5 users. Starting at 5TB up to 500TB. Big discount for first-time signup.
- 5TB
- Monthly Plan storage starts at 1.25TB up to 50TB Unlimited users, multiple computers and servers. NAS devices. 250GB storage. Starting at 250GB up to 50TB. Large discount for first-time signup.
- 250GB
- 5TB
Filen
Filen is a relatively young cloud storage service, which is why we’re tentatively giving it an honorable mention. It seems very promising despite its age, though, with a high degree of security bolstered by full-coverage client-side encryption and open-source apps.
Filen comes with 10GB of free storage by default, but you can expand that to 20GB if you sign up via our exclusive deal by clicking on any of the links in the pricing table below. Filen’s paid plans are affordable, with 2TB of storage costing $7.50 per month on a yearly plan. Read our full Filen review for more.
- 20GB
- *prices are in Euro
- 100GB
- *prices are in Euro
- 200GB
More plans
- *prices are in Euro
- 500GB
- *prices are in Euro
- 2TB
- *prices are in Euro
- 10TB
Methodology: How We Tested the Most Secure Cloud Storage Providers
Before putting pen to paper, our team of expert reviewers spends a week or more familiarizing themselves with the services we review. We go over every detail and try to use each feature available to its fullest to get to the nuts and bolts.
- Speed: We run regular speed tests on a virtual machine hosted in Ireland with a connection speed of 100 Mbps for uploads and downloads. We upload and download a 5GB test folder twice and average the results.
- Security and privacy: We examine each service’s implementation of cryptography, including encryption protocols, use of client-side encryption and server security. We also examine the privacy policy and look at the jurisdiction under which the service operates to get a full picture of its privacy.
- Collaboration and productivity: We look for and test collaboration features like advanced file sharing, first-party productivity tools and integrations with external productivity suites like Google Workspace and Microsoft Office.
- Ease of use: We make note of our experience using the service’s apps across multiple platforms, focusing on the elements we like, as well as any bugs or quirks.
- Price and value: We examine a service’s payment plans, including its free offering, and then compare all of the features it offers against the price to determine its ultimate value.
Why You Need Secure Online Storage
These are the key reasons why you might need secure cloud storage:
- Privacy protection: Features like end-to-end encryption and GDPR compliance protect your data from prying eyes, including the cloud storage service itself.
- Data security: Cloud storage services keep your data on secure servers that offer better protection than your personal device, as they are much less likely to succumb to malware or a cyberattack.
- Archiving and disaster recovery: Services that offer cloud backup let you archive files for long-term storage. Files stored in the cloud won’t be affected if your device breaks or falls prey to malware, letting you restore your files in the event of a disaster.
Final Thoughts
Most aspects of cloud storage security — like encryption, regulatory compliance and privacy policies — can be difficult to understand. Hopefully, we’ve helped you grasp them better and assisted you in choosing a secure cloud storage solution.
Sync.com is our top choice — it offers full-coverage zero-knowledge encryption paired with productivity integrations. You can try Sync.com with 5GB free, or try a full-featured premium plan with the assurances of the 30-day money-back guarantee.
What is your favorite secure cloud service? Have you used any of the services on our list? What was your experience with them like? Please let us know in the comments below, and as always, thank you for reading.
FAQ: Secure Cloud Providers
Sync.com is the best secure cloud storage service, offering zero-knowledge encryption; PIPEDA, HIPAA and GDPR compliance; and data duplication for disaster recovery.
The safest place to keep documents online is with a secure cloud storage provider that lets you manage documents. The best cloud document management system is Sync.com. From our research, it’s the only end-to-end encrypted cloud storage solution for private users that also offers Microsoft Office integration.
Yes, your cloud storage account can get hacked, just like any other online account. That’s why it’s important to have two-factor authentication to make sure only you can access your files.