| As of Nov 8, 2026 | Gmail | Outlook.com | Yahoo Mail |
|---|---|---|---|
| Free storage | Up to 15 GB, shared with Google Drive and Google Photos | 15 GB for email, plus 5 GB of Microsoft cloud storage | 20 GB (US) |
| What else uses it | Drive files, Photos | The 5 GB is shared by OneDrive files and photos, Outlook.com attachments and Microsoft 365 apps | Nothing listed |
| Storage upgrades in the iPhone app (App Store list) | 100 GB at $1.99, 200 GB at $2.99, Google AI Plus (2 TB) at $9.99 | Microsoft 365 Basic $1.99, Personal $9.99, Family $12.99 | 100 GB plan $1.99, 1 TB plan $9.99, Yahoo Mail Plus (200 GB) $4.99 |
| Largest paid option | 2 TB | 100 GB mailbox (Microsoft's cap); cloud storage is separate | 1 TB; Plus and a storage plan combine to up to 1.2 TB |
| iPhone app minimum iOS | 18.0 | 26.0 | 17.0 |
| App Store "used to track you" | None listed | Usage Data | Contact Info, Identifiers, Usage Data |
Apple's listing doesn't show whether these prices are monthly or yearly.
Outlook.com has two quotas
Microsoft counts email and cloud storage separately. Your 15 GB mailbox is its own pool. Outlook.com attachments, though, count against the 5 GB cloud pool you share with OneDrive and Microsoft 365 apps.
That matters because of what Microsoft's page says happens when the small pool fills: "You will not be able to send or receive email in Outlook.com, even if you have not exceeded your email storage quota." Your mailbox can be nearly empty and still stop working because of a OneDrive photo backup.
Also from that page: Deleted Items still counts until you empty it or 30 days pass, and Junk is cleared after 10 days. Mail sent to a full mailbox is returned to the sender.
When Gmail is full
Google says that when you're over quota, "Your ability to send and receive email in Gmail can be impacted." It also lists what stops outright: uploads to Drive, Photos backup, and creating new Docs, Sheets and Slides files.
The long-term rule is separate. Google says content can be removed if an account stays over quota for 2 years or longer, with at least 3 months' notice first.
When Yahoo is full
Yahoo's 20 GB is the US figure. When the mailbox is full you can't send or receive, and mail sent in the meantime "is not stored and can't be recovered." Yahoo also says messages may be deleted if an account is inactive for 12 months or more. Accounts already over the new limit get an email notice and a grace period before anything changes.
Which limit you'll hit first
On Gmail, Photos and Drive draw on the same 15 GB as mail, so your mailbox is whatever they leave.
On Outlook.com it's the 5 GB cloud pool if you use OneDrive backup or send large attachments.
Yahoo has the biggest free number, 20 GB, and nothing else competing for it. On an older iPhone, check the app first: the current Outlook app needs iOS 26.0, Gmail 18.0, Yahoo Mail 17.0.
Sources
- Google — How your Google storage works (checked Nov 8, 2026)
- Microsoft — Storage limits in Outlook.com (checked Nov 8, 2026)
- Yahoo — Yahoo Mail storage (checked Nov 8, 2026)
- Apple — Gmail (checked Nov 8, 2026)
- Apple — Microsoft Outlook (checked Nov 8, 2026)
- Apple — Yahoo Mail (checked Nov 8, 2026)
- Apple — iTunes Lookup API (minimum OS) (checked Nov 8, 2026)