Double Charge Detection

Double Charge Detection

Sometimes merchants accidentally (or fraudulently) charge you twice for the same purchase. Curl Budget monitors your transactions for suspicious duplicate charges and alerts you so you can take action quickly.

What Are Double Charges?

Double charges are separate, distinct transactions that shouldn't both exist:

• A restaurant running your card twice by mistake
• A subscription service billing you twice in one day
• A gas station authorization that posts alongside the final charge
• Potential fraud where someone duplicated your charge

Unlike duplicates (where your bank reports the same transaction twice), double charges are actually separate charges that hit your account.

How Detection Works

Curl Budget looks for suspicious patterns that indicate potential double charges:

Matching Criteria

Two transactions are flagged as potential double charges when:

1. Same merchant - Both transactions are from the same merchant (identified by Plaid merchant ID)
2. Same amount - Exact match, down to the cent
3. Within 24 hours - Transactions occurred within a configurable time window (default: 24 hours)
4. Similar descriptions - The transaction descriptions are at least 75% similar

Why These Criteria?

• Same merchant + amount catches obvious double-taps
• 24-hour window allows for processing delays while avoiding false positives from regular purchases
• 75% similarity threshold accounts for slight description variations while filtering out unrelated transactions

Viewing Double Charge Alerts

When potential double charges are detected:

Notification Alert

You'll receive a push notification alerting you to the potential issue. Tap to review the flagged transactions.

Transaction View

When viewing a transaction with potential double charges:

• You'll see a "Potential Double Charge" warning
• Tap to see the other transaction(s) flagged
• Compare details to determine if it's legitimate or an error

Managing Double Charge Alerts

After reviewing, you can mark the transactions as:

"Not a Double Charge"

If both transactions are legitimate (you actually made two purchases):

1. Open either transaction
2. View the double charge alert
3. Tap "Not a Double Charge"
4. The pair is dismissed and won't be flagged again

This is common for:

• Multiple purchases at the same store on the same day
• Separate items bought at different times
• Tips added after the initial charge

"Exclude All"

If you frequently have legitimate multiple charges from a merchant:

1. Open the transaction
2. Tap "Exclude All Double Charges"
3. All flagged pairs for this transaction are dismissed

Taking Action on Real Double Charges

If you've identified an actual fraudulent or erroneous charge:

1. Contact the merchant - Many double charges are merchant errors that can be quickly reversed
2. Contact your bank - If the merchant won't help, dispute the charge with your bank
3. Keep the alert - Don't dismiss it until the issue is resolved, so you can reference the details

Legitimate vs. Suspicious Charges

Common Legitimate Scenarios

These often trigger alerts but are normal:

• Gas stations - Authorization hold followed by final charge
• Restaurants - Initial charge, then tip adjustment
• Subscriptions - Multiple family members on same account
• Same-day shopping - Multiple trips to the same store

Suspicious Patterns

Watch out for:

• Unfamiliar merchants - Double charges from places you don't recognize
• Exact duplicates - Same amount at the same time
• Inconsistent with your habits - Charges that don't match your spending patterns

Configuration

The detection parameters are optimized for most users, but the underlying settings are:

• Time window: 24 hours (transactions must occur within this window)
• Similarity threshold: 75% (description text similarity)

These defaults balance catching real issues while minimizing false positives.

Double Charges vs. Other Detection

Double Charges vs. Duplicates

Double Charges	Duplicates
Separate charges that hit your account	Same charge reported multiple times
Money left your account twice	Money left once, bank reported twice
Contact merchant/bank to resolve	Just hide the duplicate in Curl Budget
Represents a potential error or fraud	Represents a bank reporting quirk

Double Charges vs. Transfers

Transfers are intentional movements of money between your accounts. Double charges are unintentional duplicate charges from merchants. These are completely different scenarios.

Notifications

Configure double charge alerts in notification settings:

• Enable/disable double charge notifications
• Immediate or digest delivery options
• Per-device notification preferences

Impact on Reports

Potential double charges still appear in your spending totals until you resolve them. This is intentional because:

• The money actually left your account
• You need accurate data to dispute with your bank
• Only you can determine if a refund is coming

Once resolved (via refund or dismissed as legitimate), your reports reflect reality.

Related Features

• Duplicate Detection - For bank-reported duplicates
• Push Notifications - Get alerted to potential issues
• Notification Settings - Configure your alerts