🛡 Now monitoring 61+ SaaS tools

Your SaaS tools are
charging you. You just
don't know it yet.

BillSensor detects SaaS billing emails and alerts you 7 days before any charge. Gmail users get passive detection with no account connection needed. Outlook and Microsoft 365 users connect once via the extension popup and get a full 12-month billing history scan.

🔒 Add to Chrome — It's Free See how it works →
61+
SaaS tools monitored
7 days
advance warning
$0
to get started
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⚠ Real complaints from real users

"I was charged $498 after cancelling my Mailchimp account. They kept billing me for 4 months and I had no idea."

— Trustpilot review · Mailchimp

"Zapier charged me $49 three months after I cancelled. Their system never processed the cancellation properly."

— Trustpilot review · Zapier

"Notion silently added billing seats when I invited my team. I didn't notice until my card was charged $240 extra."

— Trustpilot review · Notion

Manual tracking works.
Until it doesn't.

🧾

You find out after the money's gone

A bank statement shows the charge once it's already left your account. By then your only options are a refund request or a dispute.

📅

Calendar reminders don't survive real life

You set one for the first renewal, then forget to reset it for the next. Annual subscriptions are the easiest to lose track of entirely.

A cancellation email isn't proof anything stopped

Adobe, Mailchimp, and Zapier have all charged customers after a confirmed cancellation. Nothing tells you if it happens to you too.

📉

A spreadsheet stops getting updated

The fifth subscription gets added. The tenth doesn't. Six months later it's out of date and nobody trusts it enough to check.

How it works

Three steps to never
get blindsided again

01

Install the extension

Add BillSensor to Chrome in one click. No credit card. No personal data required to get started.

02

Detection runs automatically

Gmail users: BillSensor reads billing emails passively as you browse — no account connection, no OAuth. Outlook and Microsoft 365 users: connect once via the extension popup and BillSensor scans 12 months of billing history instantly.

03

Get alerted before charges

Receive browser notifications and email alerts 7 days before any SaaS renewal. Cancel before you're charged.

Product preview

Your complete billing
command center

Every subscription, alert, and cancellation link, visible in seconds. Shown here with sample data.

All Subscriptions · 8 active
Filter by risk score
+ Add subscription
NameCost/moDetected viaStatus
Adobe Creative Cloud $59.99 Gmail Active
Mailchimp $26.50 Outlook Renews soon
Claude $23.60 Gmail Active
See it in action

Everything BillSensor
tracks, in one place

From the extension popup to your dashboard, here's every screen you'll actually use.

BillSensor
Free
Open Gmail and click any billing or receipt email.
BillSensor detects it automatically.
Connect Outlook / Microsoft 365
+ Add Subscription Manually
YOUR SUBSCRIPTIONS
Claude
🔒 Log in for email alerts
Next charge: 25/09/2026
Cancel →  ·  Mark as Cancelled  ·  ✕ Remove
$23.60
Adobe Creative Cloud
🔒 Alert locked — Upgrade to protect
$59.99
⚡ UpgradeAccountSettings

Stop paying for tools
you forgot you had

7-Day Renewal Alerts

Get notified before every charge via Chrome notification and email. Never get surprised by a renewal again.

🚫

Post-Cancellation Monitoring

Mark a subscription as cancelled. Get warned 7 days before the expected charge date, and get an immediate alert if a billing email arrives after cancellation.

📈

Price Increase & Anomaly Detection

Detects when a tool charges more than last time and fires a "Price increased" alert. Any charge 20%+ higher than the last known amount is flagged as a suspicious spike.

🚨

Dark Pattern Detection

We score each tool's billing practices 1–10. High scorers get flagged automatically with a direct cancel link.

📋

Cancellation Records

Generate timestamped proof of cancellation as HTML or PDF. Dispute unauthorized charges with evidence.

📊

Billing History

Full history of every detected subscription and charge. Track your total SaaS spend month by month.

🔍

Auto-Detection

Finds subscriptions from 61+ SaaS tools. Gmail passive detection (no connection), Outlook daily auto re-scan (Pro), and multiple Gmail accounts supported.

🔒

Privacy First

No Gmail connection required. No OAuth. Email content is read locally and never leaves your device. No data sold. Ever.

Built to practice what we preach

Gmail users: no account connection ever required — zero OAuth access to your inbox
Outlook users: read-only connection via extension popup — BillSensor cannot send, delete, or modify emails
Email content never stored on our servers
Cancel your Pro plan in 1 click — no questions asked
No dark patterns. No hidden fees. No silent upgrades.
No ads. No data selling. Your data is yours.

What we actually store: for logged-in Pro and Business accounts, only parsed subscription details, tool name, amount, renewal date, and cancellation status, sync to our servers so we can send email alerts and keep your data available across devices. Raw email content is never stored or transmitted. Free users with no account keep everything local to their browser.

Detection Modes

Gmail or Outlook — covered either way

BillSensor works differently depending on your email provider. Both modes detect the same 61+ tools. Both alert you before charges. The difference is how detection happens.

✓ No connection required
📬

Gmail — Passive Detection

BillSensor reads billing emails as you naturally open them in Gmail. No Google account connection, no OAuth permission, no API access. Install the extension and it works immediately — nothing to set up.

  • No Gmail account connection ever
  • Email content never leaves your browser
  • Detects subscriptions as you open billing emails
  • Bulk inbox scan coming soon (Pro)
✓ Live now
📮

Outlook & Microsoft 365 — Connected Scan

Connect your Outlook or Microsoft 365 account once via the extension popup. BillSensor scans 12 months of your billing history instantly and surfaces every subscription — including ones you've long forgotten about.

  • One-time connect via extension popup
  • 12 months of billing history scanned instantly
  • Finds subscriptions you've already forgotten about
  • Daily auto re-scan (Pro) — new emails checked every day automatically
  • Read-only access — BillSensor cannot send or modify emails
🚀 Coming Next

More protection on the way

Every feature below targets a real billing abuse pattern. No fluff.

Live
💱

Multi-Currency Support

BillSensor detects currency from your billing emails and displays amounts in the currency you're actually charged in. Supported: USD, EUR, GBP, INR, AUD, CAD, SGD, and JPY.

Soon
📥

Bulk Gmail Inbox Scan (Pro)

Connect Gmail once and scan your entire billing history in seconds. Surfaces every subscription you've forgotten about — not just the ones you happen to open from today.

Soon
💬

Slack Alerts (Business Plan)

Get renewal and anomaly alerts piped directly to your team's Slack channel. No more someone on the team missing a billing notification buried in their inbox.

Further out: Yahoo Mail, bank/card connection via Plaid, and Zapier integration are planned for Phase 3.

Follow the build →
Dark Pattern Scores

Every tool rated by how hard
they make it to cancel

BillSensor scores each SaaS tool's billing practices from 1 to 10 based on verified complaints, cancellation flow audits, and Trustpilot data. The higher the score, the more aggressive their tactics.

Adobe 9 / 10

Charges an early cancellation fee of up to 50% of remaining contract value. Cancellation flow is buried and requires a phone call in some regions. Over 7,200 Trustpilot reviews, 1.2★ average.

Mailchimp 8 / 10

Continues billing after account cancellation attempts. Users report charges for 3-4 months post-cancellation with no confirmation emails. Refund process is manual and inconsistent.

Notion 6 / 10

Silently adds billing seats when team members are invited. Annual plan renewals arrive with minimal notice. Users frequently report surprise charges on annual renewal dates.

See all 61 tools rated. View the full dark pattern scorecard →

The only tracker that doesn't
need access to your Gmail

Every other subscription tracker requires you to connect your Gmail account via OAuth. That means granting an app permission to read your inbox. BillSensor doesn't ask for that.

Feature BillSensor SaaS Subscription Tracker CostLoop
Gmail OAuth required No Yes Yes
Dark pattern scores
Direct cancel links
Post-cancellation monitoring (Pro)
Cancellation records (PDF)
Outlook / Microsoft 365 support no OAuth via OAuth
Bank account connection required No No No optional CSV upload only

CostLoop offers a strong subscription-management feature set, including cancel links and Outlook support. BillSensor's core difference is architectural: Gmail detection needs no OAuth connection at all, nothing to grant, nothing to revoke.

FAQ

Common questions

Does BillSensor need access to my Gmail account?

No, not for Gmail. BillSensor uses passive detection for Gmail — it reads billing emails as you naturally open them in your inbox, with no Gmail account connection, no OAuth permission, and no API access. Your email content never leaves your browser. If you use Outlook or Microsoft 365, you connect once via the extension popup, but that connection is read-only.

Does BillSensor work with Outlook?

Yes. Outlook and Microsoft 365 are fully supported. Open the BillSensor extension popup, connect your account, and BillSensor scans 12 months of billing history instantly — surfacing every subscription, including ones you've forgotten about. The connection is read-only. BillSensor cannot send, delete, or modify any emails.

What is a dark pattern score?

BillSensor rates each SaaS tool's billing behaviour from 1 to 10 based on how aggressively they use dark patterns — things like hidden cancellation flows, forced continuity, surprise seat additions, and post-cancellation charges. A score of 8 or above means the tool has a documented history of billing abuse.

Does BillSensor need my bank account or credit card details?

No. BillSensor never connects to your bank account or payment cards. It detects subscriptions from billing emails only — no financial account access required.

Can BillSensor alert me if I'm still being charged after I cancelled?

Yes, on Pro and Business plans. Mark a subscription as cancelled and BillSensor watches two ways: a heads-up email 7 days before the original expected renewal so you can verify the cancellation went through, and an immediate alert if a new billing email shows up from that tool after your cancellation date. This directly targets tools like Mailchimp and Zapier that continue charging after cancellation.

Does BillSensor work with Notion, Adobe, Zapier, and Mailchimp?

Yes. All four are on BillSensor's 61-tool detection list and have dark pattern scores based on verified billing complaints. Adobe scores 9/10, Mailchimp 8/10.

Will BillSensor alert me before a free trial converts to paid?

Yes. When BillSensor detects a trial confirmation email, it sets a 7-day alert before the trial end date. You get a Chrome notification before the first charge hits — giving you time to cancel if you don't want to continue.

Who it's for

Built for real recurring
billing headaches

🧑‍💻

Freelancers

Track every tool you pay for without opening a spreadsheet. Know what's costing you before the invoice does.

🎨

Digital agencies

Managing subscriptions across multiple clients gets messy fast. Catch billing surprises before they eat into a project's margin.

💼

Small businesses & solopreneurs

Built for a 1-to-10 person team juggling more SaaS tools than anyone realizes, without needing a full subscription-management platform.

📧

Outlook & Microsoft 365 users

Get a full 12-month billing history the moment you connect. No other tracker builds specifically for Microsoft 365 the way BillSensor does.

Not built for enterprise procurement workflows, SSO-based discovery across 200+ person orgs, or bank and card expense management. Those need a bigger platform than this.

Reviews

What early users are saying

★★★★★ 5.0 · 6 ratings on Chrome Web Store
★★★★★

Excellent tool for tracking SaaS subscriptions! BillSensor makes it much easier to keep track of recurring SaaS payments and renewal dates. I like that it detects billing emails and provides timely reminders before charges occur, helping avoid unexpected renewals. The privacy-first approach, local email detection, and direct cancellation links are thoughtful features. A great extension for freelancers, agencies, and anyone managing multiple SaaS subscriptions.

RIMPA GOLDER · 29 Jul 2026
★★★★★

BillSensor is an incredibly useful extension for anyone who manages multiple SaaS subscriptions. It makes it easy to keep track of upcoming renewals, helps prevent unexpected charges, and provides a clear overview of recurring expenses. The interface is clean, the reminders are timely, and the cancellation links are a great addition.

Rhino's Gym · 29 Jul 2026
★★★★★

I have been using BillSensor for the last 3 days, and it's been a great experience so far. It detected all of my active subscriptions and notified me about upcoming renewals without me having to do much. Everything works locally in the browser, which gives me more confidence about privacy. I'm planning to upgrade to the Pro plan.

Lokesh Sharma · 28 Jul 2026
★★★★★

BillSensor is a fantastic Chrome extension for keeping track of SaaS subscriptions. It was quick to set up, easy to use, and the renewal reminders have already helped me avoid unexpected charges. The cancellation links and billing insights are really useful.

Buzz Six · 25 Jul 2026
★★★★★

Excellent extension! Simple to set up, easy to use, and very helpful for tracking SaaS subscriptions and recurring bills. Highly recommended!

Theprowriter One · 25 Jul 2026
★★★★★

Excellent extension.

atreye dutta · 29 Jul 2026
Pricing

Simple, honest pricing.
No asterisks.

Free
$0/month
For individuals getting started
  • Unlimited passive detection (Gmail) or 12-month scan (Outlook)
  • Up to 5 manual subscriptions
  • 7-day Chrome renewal alerts (Gmail, unlimited)
  • Email alerts on your 5 lowest-cost subscriptions
    Requires free registration. Ranked lowest-amount first, permanent once set.
  • Dark pattern scores for your 3 lowest-cost subscriptions
  • Direct cancel links for your 3 lowest-cost subscriptions
  • Delete wrongly detected subscriptions
  • Post-cancellation monitoring
  • Price increase & anomaly alerts
  • Cloud sync & billing history
  • Cancellation records (PDF)
Add to Chrome — Free
Business
$29/month
For agencies & small teams
  • All Pro features, per member
  • Up to 10 seats (admin included)
  • Admin dashboard
    Aggregated spend, renewals, and per-member subscription detail
  • Works across mixed Gmail and Outlook members
  • Invite up to 9 members by email
  • Priority support
  • 7-day free trial

14-day money-back guarantee. Cancel anytime in 1 click.

What's new

Actively built, actively shipped

Last updated August 2026

Outlook / Microsoft 365 support

Connect Outlook or Microsoft 365 for a full 12-month inbox scan via Microsoft Graph API. Pro and Business get automatic daily re-scanning in the background.

Post-cancellation monitoring (Pro & Business)

Mark a subscription cancelled and BillSensor watches two ways: a heads-up email 7 days before the original renewal date, and an immediate alert if a billing email shows up anyway.

Price increase & anomaly detection (Pro & Business)

Get notified the moment a tool raises its price, or if a charge lands 20%+ higher than what you paid last time.

Business plan

One admin, up to 9 members, each connecting their own Gmail or Outlook independently. The admin dashboard shows every member's subscriptions, spend, and upcoming renewals in one place.

Personal Dashboard (Pro & Business)

A dedicated web dashboard alongside the extension: monthly spend, renewals this month, full subscription history, manual add, and CSV import for bulk-adding existing subscriptions.

Cancellation records

Download a timestamped record proving when you cancelled a subscription, useful evidence if a company charges you after the fact.

Smarter free tier alerts

Free users get email renewal alerts on their 5 lowest-cost subscriptions, with cancel links and dark pattern scores unlocked for the 3 cheapest of those.

3-day renewal alerts (Pro & Business)

On top of the standard 7-day warning, a second alert fires 3 days before a charge hits, a final chance to cancel or block the payment.

Multi-currency detection

Recognizes and displays amounts in USD, EUR, GBP, INR, and other major currencies with the correct symbol.

Works everywhere Chrome does

Confirmed compatibility with Edge, Brave, Opera, and other Chromium-based browsers, not just Chrome.