Introduction to Signal

Explore API

Plaid Signal allows you to evaluate the likelihood of a specific ACH transaction resulting in a return. Signal is powered by a machine learning model trained on Plaid’s consumer-permissioned data network, including over 1,000 risk factors. Signal provides two overall risk assessment scores, along with associated risk tiers and nearly 40 predictive insights that you can incorporate into your own risk assessment models. By using the Signal API, you can release funds earlier to optimize your user experience while managing the risk of ACH returns.

Signal is intended to be used alongside Auth. Once you have obtained an access_token initialized for the Auth product, this token can be used with Signal endpoints. Signal does not require initializing Link with any product beyond auth.

The Signal API consists of three routes and one optional route:

/signal/evaluate: Call this endpoint before initiating an ACH transaction to get the return risk assessment and additional risk signals.

/signal/decision/report: After calling /signal/evaluate, call this endpoint to inform Plaid of your risk and payment decision outcome and whether or not you executed the ACH transaction. Your decision feedback will help the model to optimize for your use case.

/signal/return/report: Call this endpoint when you receive a return for the ACH transaction you previously called the /signal/evaluate endpoint for. Your feedback allows the model to incorporate the latest risk trends into its assessments.

/signal/prepare (optional): Call this endpoint to add Signal to an Item when Signal was not an initialized product when creating a link token.

1. Using /link/token/create, create a Link token initialized with the auth product, and use this token to launch Link.
2. The end user completes the Link flow by logging into their financial institution.
3. Use /item/public_token/exchange to exchange the public_token returned from Link's onSuccess callback for an access_token.
4. Call /accounts/get using the access_token returned in the previous step to obtain the account_id of the account you will be evaluating.
5. Call /signal/evaluate using the access_token and account_id obtained in the previous steps.
6. Based on the data returned by /signal/evaluate, decide whether to proceed directly with the transfer or apply an additional risk mitigation layer. You may either use the risk scoring and tier data returned by /signal/evaluate or use the core_attributes and feed them into your own model, along with additional information you may have about the user.
7. If you decide to proceed with the transfer, initiate it as you normally would using Plaid Auth endpoints. For more details, see Auth.
8. Report your decision following the risk assessment and whether or not to proceed with the transfer by calling /signal/decision/report.
9. If the transfer is later returned, call /signal/return/report.

Signal provides two categories of risk -- customer-initiated return risk, which corresponds to ACH returns initiated by customers (unauthorized ACH returns), and bank-initiated return risk (primarily NSFs and administrative returns), which corresponds to ACH returns initiated by financial institutions. Each risk category has a score ranging from 1-99 and a corresponding risk tier to help you better understand the associated level of return risk.

In addition to the risk scores and tiers, Signal also provides more than 60 predictive insights to help provide even greater visibility into the factors contributing to a given score and tier. You may choose to incorporate these insights into your own risk models.

For more details on the data returned by Signal, see the Signal API reference.

1{
2  "scores": {
3    "customer_initiated_return_risk": {
4      "score": 9,
5      "risk_tier": 1
6    },
7    "bank_initiated_return_risk": {
8      "score": 72,
9      "risk_tier": 7
10    }
11  },
12  "core_attributes": {
13    "days_since_first_plaid_connection": 510,
14    "plaid_connections_count_7d": 6,
15    "plaid_connections_count_30d": 7,
16    "total_plaid_connections_count": 15,
17    "is_savings_or_money_market_account": false,
18    ...
19  },
20  "request_id": "mdqfuVxeoza6mhu"
21}

Signal endpoints are not enabled in the Sandbox environment by default. To request access to Signal endpoints, contact Sales or reach to to your Plaid Account Manager.

If you're ready to launch to Production, see the Launch checklist.