Compare Outlook.com and Proton Mail free tiers side by side. Pricing, limits, change history, and risk assessment for developers.
We are not publishing a free-tier verdict for either Outlook.com or Proton Mail. We could not read the page we cite for Outlook.com when we last looked, on 2026-11-11. The only record that would rate Proton Mail is a change we could not check against an archived copy of Proton Mail's page, so we are not publishing a rating for it. We are not publishing a stability rating for Proton Mail. We are not comparing the two pricing histories.
A verdict here is not a fixed property of the vendor. A one-off pricing event demotes a vendor while its recorded date falls in the last 180 days and then lapses on its own, with nothing about the vendor having changed; a standing condition — a free tier withdrawn and not restored, a product retired — does not lapse with time. A badge carrying a date states the record it rests on; a badge with no date rests on no record in force.
No recorded pricing changes for Outlook.com.
We do not push notifications. Every change we record is readable the moment it lands, and the JSON answer carries an ETag — send it back as If-None-Match and an unchanged answer costs one 304.
curl https://agentdeals.dev/api/changes?vendor=Outlook.com
curl https://agentdeals.dev/pricing-changes/feed.xml?vendor=Outlook.com
curl https://agentdeals.dev/api/changes?vendor=Proton%20Mail
curl https://agentdeals.dev/pricing-changes/feed.xml?vendor=Proton%20Mail