Introduction to Signal
Assess the return risk of an ACH debit transaction
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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, and is designed to provide a result in under one second. Signal provides two overall risk assessment scores, along with associated risk tiers and over 60 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.
Usage
Signal is intended to be used alongside 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): This endpoint is intended for customers who use Signal alongside Identity. In the specific scenario when /identity/get
is called immediately after linking an Item, but the Item was not configured with Signal or Identity upon its creation, calling /signal/prepare
immediately after /identity/get
can reduce latency.
Sample flow
- Using
/link/token/create
, create a Link token initialized with theauth
andsignal
products, and use this token to launch Link. - The end user completes the Link flow by logging into their financial institution.
- Use
/item/public_token/exchange
to exchange thepublic_token
returned from Link'sonSuccess
callback for anaccess_token
. - Call
/accounts/get
using theaccess_token
returned in the previous step to obtain theaccount_id
of the account you will be evaluating. - Call
/signal/evaluate
using theaccess_token
andaccount_id
obtained in the previous steps. - 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 thecore_attributes
and feed them into your own model, along with additional information you may have about the user and the proposed transaction. For potentially high-risk transactions, you can also call/accounts/balance/get
at this point to obtain real-time balance information and use it as another input into your decision. - If you decide to proceed with the transfer, initiate it as you normally would using Plaid Auth endpoints. For more details, see Auth.
- Report your decision following the risk assessment and whether or not to proceed with the transfer by calling
/signal/decision/report
. - If the transfer is later returned, call
/signal/return/report
.
Signal data
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": 16 },7 "bank_initiated_return_risk": {8 "score": 72,9 "risk_tier": 710 }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 Dashboard
To help you monitor your ACH returns and performance, Plaid provides a Signal Dashboard within the Plaid Dashboard. You can access the Signal Dashboard after receiving production access to Signal. On the Dashboard, you can view ACH returns and causes over time, as well as view the details of individual transactions. You can also use the Dashboard to model and backtest the impact of different Signal score risk thresholds on your return rates.


Testing Signal
You can test Signal in the Sandbox and Development environments. Note that the /sandbox/public_token/create
endpoint does not allow signal
in the initial_products
array; for testing with this endpoint, put auth
in the initial_products
array instead, then proceed to call the Signal endpoints as normal.
Next steps
To request access to Signal in Production, contact Sales.
If you're ready to launch to Production, see the Launch checklist.