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Add Rate to Rate Card

Billing & Ledger Service API (1.0.0)

The Billing & Ledger Service is the financial engine of the NPS Billing Platform. It manages pricing (Rates, Rate Cards), subscription configurations, allocation rules for split billing scenarios (divorced households, subsidies), charge lifecycle, and double-entry accounting ledger.

Key Concepts

Charge Lifecycle

Charges follow a strict lifecycle with immutability after invoicing:

  • PENDING → Created but not validated
  • BILLED → Validated and ready to invoice (still editable)
  • INVOICED → Invoiced (IMMUTABLE - moved to SettledCharge)
  • PAID → Paid directly without invoice
  • VOID → Cancelled

Allocation Configuration

Defines how charges are split between multiple accounts (e.g., divorced parents, subsidy agencies). Three rule types:

  • RESPONSIBLE_PARTY: Percentage-based split
  • COVERAGE_TRANSFER: Fixed amount covered (e.g., $25 subsidy per charge)
  • BILLING_CAP: Maximum amount per period

Double-Entry Ledger

All financial transactions follow the accounting equation (Debits = Credits). Journal entries are immutable once created - corrections use adjustment entries.

Monetary Values

All monetary amounts are stored as DECIMAL type in cents (e.g., 5000 = $50.00). Use DECIMAL or NUMERIC type (BigDecimal in Java) for precision and to avoid rounding errors. Never use integers or floating-point for money.

Download OpenAPI description
billing-ledger-service.json
billing-ledger-service.yaml
Languages
Servers
Mock server
https://docs.nelnetpay.com/_mock/apis/billing-ledger-service
UAT server
https://api.uat.nelnetpay.com/billing
Production server
https://api.nelnetpay.com/billing

Rates

Manage rate catalog (pricing for services)

Operations

RateCards

Manage rate card groupings for UI organization

Operations

List Rate Cards

Request

List all rate cards for the authenticated merchant. Rate cards group related rates for easier UI presentation and selection.

Security
OAuth2
Query
scopestring

Filter by rate card scope

Enum"MERCHANT""ACCOUNT"
pageinteger>= 1

Page number (1-indexed)

Default 1
Example: page=1
page_sizeinteger[ 1 .. 200 ]

Number of items per page

Default 50
Example: page_size=50
curl -i -X GET \
  'https://docs.nelnetpay.com/_mock/apis/billing-ledger-service/rateCards?scope=MERCHANT&page=1&page_size=50' \
  -H 'Authorization: Bearer <YOUR_TOKEN_HERE>'

Responses

Successful response

Bodyapplication/json
resultsArray of objectsrequired
results[].​idstring(uuid)required
results[].​entityIdstring(uuid)required
results[].​namestringrequired
results[].​scopestringrequired

Scope of rate card availability

Enum"MERCHANT""ACCOUNT"
results[].​tagsobject
results[].​optimisticLockVersioninteger(int64)read-only

Optimistic locking version (managed by Hibernate @Version). Prevents concurrent update conflicts.

results[].​createdAtstring(date-time)required
results[].​updatedAtstring(date-time)
paginationobjectrequired
pagination.​totalRecordsintegerrequired

Total number of records across all pages

Example: 100
pagination.​currentPageintegerrequired

Current page number (1-indexed)

Example: 1
pagination.​totalPagesintegerrequired

Total number of pages

Example: 10
pagination.​nextPageinteger or null

Next page number, null if on last page

Example: 2
pagination.​prevPageinteger or null

Previous page number, null if on first page

Example: null
Response
application/json
{
  "results": [
    { … }
  ],
  "pagination": {
    "totalRecords": 100,
    "currentPage": 1,
    "totalPages": 10,
    "nextPage": 2,
    "prevPage": null
  }
}

Create Rate Card

Request

Create a new rate card to group related rates.

Scope:

  • MERCHANT - Available to all accounts
  • ACCOUNT - Available to specific accounts only
Security
OAuth2
Bodyapplication/jsonrequired
namestring<= 255 charactersrequired
scopestringrequired

Scope of rate card availability

Enum"MERCHANT""ACCOUNT"
tagsobject
curl -i -X POST \
  https://docs.nelnetpay.com/_mock/apis/billing-ledger-service/rateCards \
  -H 'Authorization: Bearer <YOUR_TOKEN_HERE>' \
  -H 'Content-Type: application/json' \
  -d '{
    "name": "Pre-K Rates 2026",
    "scope": "MERCHANT",
    "tags": {
      "billing.program": "PRE_K",
      "billing.year": "2026"
    }
  }'

Responses

Rate card created successfully

Bodyapplication/json
idstring(uuid)required
entityIdstring(uuid)required
namestringrequired
scopestringrequired

Scope of rate card availability

Enum"MERCHANT""ACCOUNT"
tagsobject
optimisticLockVersioninteger(int64)read-only

Optimistic locking version (managed by Hibernate @Version). Prevents concurrent update conflicts.

createdAtstring(date-time)required
updatedAtstring(date-time)
Response
application/json
{
  "id": "497f6eca-6276-4993-bfeb-53cbbbba6f08",
  "entityId": "156e622c-6cdf-4c27-9bc9-2f2db69919f5",
  "name": "string",
  "scope": "MERCHANT",
  "tags": {
    "property1": "string",
    "property2": "string"
  },
  "optimisticLockVersion": 0,
  "createdAt": "2019-08-24T14:15:22Z",
  "updatedAt": "2019-08-24T14:15:22Z"
}

Get Rate Card Details

Request

Retrieve details of a specific rate card including associated rates

Security
OAuth2
Path
rateCardIdstring(uuid)required

Unique identifier for the rate card

curl -i -X GET \
  'https://docs.nelnetpay.com/_mock/apis/billing-ledger-service/rateCards/{rateCardId}' \
  -H 'Authorization: Bearer <YOUR_TOKEN_HERE>'

Responses

Successful response

Bodyapplication/json
idstring(uuid)required
entityIdstring(uuid)required
namestringrequired
scopestringrequired

Scope of rate card availability

Enum"MERCHANT""ACCOUNT"
tagsobject
optimisticLockVersioninteger(int64)read-only

Optimistic locking version (managed by Hibernate @Version). Prevents concurrent update conflicts.

createdAtstring(date-time)required
updatedAtstring(date-time)
ratesArray of objects
Response
application/json
{
  "id": "497f6eca-6276-4993-bfeb-53cbbbba6f08",
  "entityId": "156e622c-6cdf-4c27-9bc9-2f2db69919f5",
  "name": "string",
  "scope": "MERCHANT",
  "tags": {
    "property1": "string",
    "property2": "string"
  },
  "optimisticLockVersion": 0,
  "createdAt": "2019-08-24T14:15:22Z",
  "updatedAt": "2019-08-24T14:15:22Z",
  "rates": [
    { … }
  ]
}

Update Rate Card

Request

Update a rate card's information (partial update)

Security
OAuth2
Path
rateCardIdstring(uuid)required

Unique identifier for the rate card

Bodyapplication/jsonrequired
namestring<= 255 characters
scopestring

Scope of rate card availability

Enum"MERCHANT""ACCOUNT"
tagsobject
curl -i -X PATCH \
  'https://docs.nelnetpay.com/_mock/apis/billing-ledger-service/rateCards/{rateCardId}' \
  -H 'Authorization: Bearer <YOUR_TOKEN_HERE>' \
  -H 'Content-Type: application/json' \
  -d '{
    "name": "string",
    "scope": "MERCHANT",
    "tags": {
      "property1": "string",
      "property2": "string"
    }
  }'

Responses

Rate card updated successfully

Bodyapplication/json
idstring(uuid)required
entityIdstring(uuid)required
namestringrequired
scopestringrequired

Scope of rate card availability

Enum"MERCHANT""ACCOUNT"
tagsobject
optimisticLockVersioninteger(int64)read-only

Optimistic locking version (managed by Hibernate @Version). Prevents concurrent update conflicts.

createdAtstring(date-time)required
updatedAtstring(date-time)
Response
application/json
{
  "id": "497f6eca-6276-4993-bfeb-53cbbbba6f08",
  "entityId": "156e622c-6cdf-4c27-9bc9-2f2db69919f5",
  "name": "string",
  "scope": "MERCHANT",
  "tags": {
    "property1": "string",
    "property2": "string"
  },
  "optimisticLockVersion": 0,
  "createdAt": "2019-08-24T14:15:22Z",
  "updatedAt": "2019-08-24T14:15:22Z"
}

Delete Rate Card

Request

Delete a rate card (does not delete associated rates)

Security
OAuth2
Path
rateCardIdstring(uuid)required

Unique identifier for the rate card

curl -i -X DELETE \
  'https://docs.nelnetpay.com/_mock/apis/billing-ledger-service/rateCards/{rateCardId}' \
  -H 'Authorization: Bearer <YOUR_TOKEN_HERE>'

Responses

Rate card deleted successfully

Response
No content

Add Rate to Rate Card

Request

Associate a rate with a rate card (idempotent)

Security
OAuth2
Path
rateCardIdstring(uuid)required

Unique identifier for the rate card

rateIdstring(uuid)required

Unique identifier for the rate

Bodyapplication/json
displayOrderinteger

Order in which rate appears in the card (lower = first)

Default 0
curl -i -X POST \
  'https://docs.nelnetpay.com/_mock/apis/billing-ledger-service/rateCards/{rateCardId}/rates/{rateId}' \
  -H 'Authorization: Bearer <YOUR_TOKEN_HERE>' \
  -H 'Content-Type: application/json' \
  -d '{
    "displayOrder": 0
  }'

Responses

Rate added to rate card successfully

Bodyapplication/json
rateCardIdstring(uuid)required
rateIdstring(uuid)required
displayOrderinteger
createdAtstring(date-time)required
Response
application/json
{
  "rateCardId": "851fa573-2930-442a-9510-162bc54b330a",
  "rateId": "dc6263b0-e8fb-4144-a111-53fde6c86836",
  "displayOrder": 0,
  "createdAt": "2019-08-24T14:15:22Z"
}

Remove Rate from Rate Card

Request

Remove a rate from a rate card (idempotent)

Security
OAuth2
Path
rateCardIdstring(uuid)required

Unique identifier for the rate card

rateIdstring(uuid)required

Unique identifier for the rate

curl -i -X DELETE \
  'https://docs.nelnetpay.com/_mock/apis/billing-ledger-service/rateCards/{rateCardId}/rates/{rateId}' \
  -H 'Authorization: Bearer <YOUR_TOKEN_HERE>'

Responses

Rate removed from rate card successfully

Response
No content

Subscriptions

Manage billable entity subscriptions to rates

Operations

AllocationConfigurations

Manage charge allocation configurations for split billing

Operations

Charges

Manage billable charges (mutable pre-invoice state)

Operations

SettledCharges

Query settled charges (immutable post-invoice state)

Operations

Refunds

Manage refunds for invoices, charges, or standalone refunds

Operations

Adjustments

Manage manual adjustments and corrections

Operations

Ledger

Manage double-entry accounting ledger

Operations
Webhooks

Exports

Export data in CSV format for GL integrations

Operations