diff --git a/core/api/dev/apollo-federation/supergraph.graphql b/core/api/dev/apollo-federation/supergraph.graphql
index 0120d4f607c..eb736dc1fba 100644
--- a/core/api/dev/apollo-federation/supergraph.graphql
+++ b/core/api/dev/apollo-federation/supergraph.graphql
@@ -184,7 +184,7 @@ type BTCWallet implements Wallet
   """An unconfirmed incoming onchain balance."""
   pendingIncomingBalance: SignedAmount!
   transactionById(transactionId: ID!): Transaction!
-  transactionByPaymentHash(paymentHash: PaymentHash!): Transaction!
+  transactionByPaymentHash(paymentHash: PaymentHash!): Transaction
 
   """A list of BTC transactions associated with this wallet."""
   transactions(
@@ -550,11 +550,19 @@ input IntraLedgerUsdPaymentSendInput
   walletId: WalletId!
 }
 
-union Invoice
+"""A lightning invoice."""
+interface Invoice
   @join__type(graph: PUBLIC)
-  @join__unionMember(graph: PUBLIC, member: "LnInvoice")
-  @join__unionMember(graph: PUBLIC, member: "LnNoAmountInvoice")
- = LnInvoice | LnNoAmountInvoice
+{
+  """The payment hash of the lightning invoice."""
+  paymentHash: PaymentHash!
+
+  """The bolt11 invoice to be paid."""
+  paymentRequest: LnPaymentRequest!
+
+  """The payment secret of the lightning invoice."""
+  paymentSecret: LnPaymentSecret!
+}
 
 enum InvoicePaymentStatus
   @join__type(graph: PUBLIC)
@@ -587,7 +595,8 @@ enum link__Purpose {
   EXECUTION
 }
 
-type LnInvoice
+type LnInvoice implements Invoice
+  @join__implements(graph: PUBLIC, interface: "Invoice")
   @join__type(graph: PUBLIC)
 {
   paymentHash: PaymentHash!
@@ -671,7 +680,8 @@ type LnInvoicePaymentStatusPayload
   status: InvoicePaymentStatus
 }
 
-type LnNoAmountInvoice
+type LnNoAmountInvoice implements Invoice
+  @join__implements(graph: PUBLIC, interface: "Invoice")
   @join__type(graph: PUBLIC)
 {
   paymentHash: PaymentHash!
@@ -1598,7 +1608,7 @@ type UsdWallet implements Wallet
   """An unconfirmed incoming onchain balance."""
   pendingIncomingBalance: SignedAmount!
   transactionById(transactionId: ID!): Transaction!
-  transactionByPaymentHash(paymentHash: PaymentHash!): Transaction!
+  transactionByPaymentHash(paymentHash: PaymentHash!): Transaction
   transactions(
     """Returns the items in the list that come after the specified cursor."""
     after: String
@@ -1919,7 +1929,7 @@ interface Wallet
   transactionByPaymentHash(
     """The payment hash of the lightning invoice paid in this transaction."""
     paymentHash: PaymentHash!
-  ): Transaction!
+  ): Transaction
 
   """
   Transactions are ordered anti-chronologically,
diff --git a/core/api/src/graphql/admin/schema.graphql b/core/api/src/graphql/admin/schema.graphql
index 6d4504a45dd..ee004274a5e 100644
--- a/core/api/src/graphql/admin/schema.graphql
+++ b/core/api/src/graphql/admin/schema.graphql
@@ -86,7 +86,7 @@ type BTCWallet implements Wallet {
   """An unconfirmed incoming onchain balance."""
   pendingIncomingBalance: SignedAmount!
   transactionById(transactionId: ID!): Transaction!
-  transactionByPaymentHash(paymentHash: PaymentHash!): Transaction!
+  transactionByPaymentHash(paymentHash: PaymentHash!): Transaction
 
   """A list of BTC transactions associated with this wallet."""
   transactions(
@@ -175,7 +175,17 @@ type InitiationViaOnChain {
   address: OnChainAddress!
 }
 
-union Invoice = LnInvoice | LnNoAmountInvoice
+"""A lightning invoice."""
+interface Invoice {
+  """The payment hash of the lightning invoice."""
+  paymentHash: PaymentHash!
+
+  """The bolt11 invoice to be paid."""
+  paymentRequest: LnPaymentRequest!
+
+  """The payment secret of the lightning invoice."""
+  paymentSecret: LnPaymentSecret!
+}
 
 scalar Language
 
@@ -201,19 +211,6 @@ type LightningPayment {
   status: LnPaymentStatus
 }
 
-type LnInvoice {
-  paymentHash: PaymentHash!
-  paymentRequest: LnPaymentRequest!
-  paymentSecret: LnPaymentSecret!
-  satoshis: SatAmount
-}
-
-type LnNoAmountInvoice {
-  paymentHash: PaymentHash!
-  paymentRequest: LnPaymentRequest!
-  paymentSecret: LnPaymentSecret!
-}
-
 scalar LnPaymentPreImage
 
 """BOLT11 lightning invoice payment request with the amount included"""
@@ -416,7 +413,7 @@ type UsdWallet implements Wallet {
   """An unconfirmed incoming onchain balance."""
   pendingIncomingBalance: SignedAmount!
   transactionById(transactionId: ID!): Transaction!
-  transactionByPaymentHash(paymentHash: PaymentHash!): Transaction!
+  transactionByPaymentHash(paymentHash: PaymentHash!): Transaction
   transactions(
     """Returns the items in the list that come after the specified cursor."""
     after: String
@@ -475,7 +472,7 @@ interface Wallet {
   transactionByPaymentHash(
     """The payment hash of the lightning invoice paid in this transaction."""
     paymentHash: PaymentHash!
-  ): Transaction!
+  ): Transaction
 
   """
   Transactions are ordered anti-chronologically,
diff --git a/core/api/src/graphql/public/schema.graphql b/core/api/src/graphql/public/schema.graphql
index 7c0ad668bc6..fe64bc01873 100644
--- a/core/api/src/graphql/public/schema.graphql
+++ b/core/api/src/graphql/public/schema.graphql
@@ -127,7 +127,7 @@ type BTCWallet implements Wallet {
   """An unconfirmed incoming onchain balance."""
   pendingIncomingBalance: SignedAmount!
   transactionById(transactionId: ID!): Transaction!
-  transactionByPaymentHash(paymentHash: PaymentHash!): Transaction!
+  transactionByPaymentHash(paymentHash: PaymentHash!): Transaction
 
   """A list of BTC transactions associated with this wallet."""
   transactions(
@@ -420,7 +420,17 @@ input IntraLedgerUsdPaymentSendInput {
   walletId: WalletId!
 }
 
-union Invoice = LnInvoice | LnNoAmountInvoice
+"""A lightning invoice."""
+interface Invoice {
+  """The payment hash of the lightning invoice."""
+  paymentHash: PaymentHash!
+
+  """The bolt11 invoice to be paid."""
+  paymentRequest: LnPaymentRequest!
+
+  """The payment secret of the lightning invoice."""
+  paymentSecret: LnPaymentSecret!
+}
 
 enum InvoicePaymentStatus {
   EXPIRED
@@ -430,7 +440,7 @@ enum InvoicePaymentStatus {
 
 scalar Language
 
-type LnInvoice {
+type LnInvoice implements Invoice {
   paymentHash: PaymentHash!
   paymentRequest: LnPaymentRequest!
   paymentSecret: LnPaymentSecret!
@@ -498,7 +508,7 @@ type LnInvoicePaymentStatusPayload {
   status: InvoicePaymentStatus
 }
 
-type LnNoAmountInvoice {
+type LnNoAmountInvoice implements Invoice {
   paymentHash: PaymentHash!
   paymentRequest: LnPaymentRequest!
   paymentSecret: LnPaymentSecret!
@@ -1255,7 +1265,7 @@ type UsdWallet implements Wallet {
   """An unconfirmed incoming onchain balance."""
   pendingIncomingBalance: SignedAmount!
   transactionById(transactionId: ID!): Transaction!
-  transactionByPaymentHash(paymentHash: PaymentHash!): Transaction!
+  transactionByPaymentHash(paymentHash: PaymentHash!): Transaction
   transactions(
     """Returns the items in the list that come after the specified cursor."""
     after: String
@@ -1508,7 +1518,7 @@ interface Wallet {
   transactionByPaymentHash(
     """The payment hash of the lightning invoice paid in this transaction."""
     paymentHash: PaymentHash!
-  ): Transaction!
+  ): Transaction
 
   """
   Transactions are ordered anti-chronologically,
diff --git a/core/api/src/graphql/shared/types/abstract/invoice.ts b/core/api/src/graphql/shared/types/abstract/invoice.ts
index 96081531f4c..b6c16c823f8 100644
--- a/core/api/src/graphql/shared/types/abstract/invoice.ts
+++ b/core/api/src/graphql/shared/types/abstract/invoice.ts
@@ -1,12 +1,27 @@
-import LnInvoice from "../object/ln-invoice"
+import PaymentHash from "../scalar/payment-hash"
+import LnPaymentRequest from "../scalar/ln-payment-request"
 
-import { GT } from "@/graphql/index"
+import LnPaymentSecret from "../scalar/ln-payment-secret"
 
-import LnNoAmountInvoice from "@/graphql/shared/types/object/ln-noamount-invoice"
+import { GT } from "@/graphql/index"
 
-const Invoice = GT.Union({
+const IInvoice = GT.Interface({
   name: "Invoice",
-  types: () => [LnInvoice, LnNoAmountInvoice],
+  description: "A lightning invoice.",
+  fields: () => ({
+    paymentRequest: {
+      type: GT.NonNull(LnPaymentRequest),
+      description: "The bolt11 invoice to be paid.",
+    },
+    paymentHash: {
+      type: GT.NonNull(PaymentHash),
+      description: "The payment hash of the lightning invoice.",
+    },
+    paymentSecret: {
+      type: GT.NonNull(LnPaymentSecret),
+      description: "The payment secret of the lightning invoice.",
+    },
+  }),
 })
 
-export default Invoice
+export default IInvoice
diff --git a/core/api/src/graphql/shared/types/abstract/wallet.ts b/core/api/src/graphql/shared/types/abstract/wallet.ts
index ebf56cd5758..6690c69912d 100644
--- a/core/api/src/graphql/shared/types/abstract/wallet.ts
+++ b/core/api/src/graphql/shared/types/abstract/wallet.ts
@@ -6,7 +6,7 @@ import SignedAmount from "../scalar/signed-amount"
 import OnChainAddress from "../scalar/on-chain-address"
 import PaymentHash from "../scalar/payment-hash"
 
-import Invoice from "./invoice"
+import IInvoice from "./invoice"
 
 import { connectionArgs } from "@/graphql/connections"
 import { GT } from "@/graphql/index"
@@ -49,7 +49,7 @@ const IWallet = GT.Interface({
       },
     },
     invoiceByPaymentHash: {
-      type: GT.NonNull(Invoice),
+      type: GT.NonNull(IInvoice),
       args: {
         paymentHash: {
           type: GT.NonNull(PaymentHash),
@@ -59,7 +59,7 @@ const IWallet = GT.Interface({
       },
     },
     transactionByPaymentHash: {
-      type: GT.NonNull(Transaction),
+      type: Transaction,
       args: {
         paymentHash: {
           type: GT.NonNull(PaymentHash),
diff --git a/core/api/src/graphql/shared/types/object/btc-wallet.ts b/core/api/src/graphql/shared/types/object/btc-wallet.ts
index c50d66d9344..377fb137aff 100644
--- a/core/api/src/graphql/shared/types/object/btc-wallet.ts
+++ b/core/api/src/graphql/shared/types/object/btc-wallet.ts
@@ -8,7 +8,7 @@ import OnChainAddress from "../scalar/on-chain-address"
 
 import PaymentHash from "../scalar/payment-hash"
 
-import Invoice from "../abstract/invoice"
+import IInvoice from "../abstract/invoice"
 
 import Transaction, { TransactionConnection } from "./transaction"
 
@@ -130,7 +130,7 @@ const BtcWallet = GT.Object<Wallet>({
       },
     },
     invoiceByPaymentHash: {
-      type: GT.NonNull(Invoice),
+      type: GT.NonNull(IInvoice),
       args: {
         paymentHash: {
           type: GT.NonNull(PaymentHash),
@@ -153,7 +153,7 @@ const BtcWallet = GT.Object<Wallet>({
       },
     },
     transactionByPaymentHash: {
-      type: GT.NonNull(Transaction),
+      type: Transaction,
       args: {
         paymentHash: {
           type: GT.NonNull(PaymentHash),
diff --git a/core/api/src/graphql/shared/types/object/ln-invoice.ts b/core/api/src/graphql/shared/types/object/ln-invoice.ts
index df1dfb172da..7d914f86cd6 100644
--- a/core/api/src/graphql/shared/types/object/ln-invoice.ts
+++ b/core/api/src/graphql/shared/types/object/ln-invoice.ts
@@ -3,10 +3,13 @@ import PaymentHash from "../scalar/payment-hash"
 import LnPaymentSecret from "../scalar/ln-payment-secret"
 import SatAmount from "../scalar/sat-amount"
 
+import IInvoice from "../abstract/invoice"
+
 import { GT } from "@/graphql/index"
 
 const LnInvoice = GT.Object<WalletInvoice>({
   name: "LnInvoice",
+  interfaces: () => [IInvoice],
   isTypeOf: (source) => !!source.lnInvoice.amount,
   fields: () => ({
     paymentRequest: {
diff --git a/core/api/src/graphql/shared/types/object/ln-noamount-invoice.ts b/core/api/src/graphql/shared/types/object/ln-noamount-invoice.ts
index ddbd7f04c07..49ebed19b53 100644
--- a/core/api/src/graphql/shared/types/object/ln-noamount-invoice.ts
+++ b/core/api/src/graphql/shared/types/object/ln-noamount-invoice.ts
@@ -2,11 +2,14 @@ import LnPaymentRequest from "../scalar/ln-payment-request"
 import PaymentHash from "../scalar/payment-hash"
 import LnPaymentSecret from "../scalar/ln-payment-secret"
 
+import IInvoice from "../abstract/invoice"
+
 import { GT } from "@/graphql/index"
 // import InvoicePaymentStatus from "../scalar/invoice-payment-status"
 
 const LnNoAmountInvoice = GT.Object<WalletInvoice>({
   name: "LnNoAmountInvoice",
+  interfaces: () => [IInvoice],
   isTypeOf: (source) => !source.lnInvoice.amount,
   fields: () => ({
     paymentRequest: {
diff --git a/core/api/src/graphql/shared/types/object/usd-wallet.ts b/core/api/src/graphql/shared/types/object/usd-wallet.ts
index cfb6e27f830..d63415658ff 100644
--- a/core/api/src/graphql/shared/types/object/usd-wallet.ts
+++ b/core/api/src/graphql/shared/types/object/usd-wallet.ts
@@ -8,7 +8,7 @@ import OnChainAddress from "../scalar/on-chain-address"
 
 import PaymentHash from "../scalar/payment-hash"
 
-import Invoice from "../abstract/invoice"
+import IInvoice from "../abstract/invoice"
 
 import Transaction, { TransactionConnection } from "./transaction"
 
@@ -128,7 +128,7 @@ const UsdWallet = GT.Object<Wallet>({
       },
     },
     invoiceByPaymentHash: {
-      type: GT.NonNull(Invoice),
+      type: GT.NonNull(IInvoice),
       args: {
         paymentHash: {
           type: GT.NonNull(PaymentHash),
@@ -151,7 +151,7 @@ const UsdWallet = GT.Object<Wallet>({
       },
     },
     transactionByPaymentHash: {
-      type: GT.NonNull(Transaction),
+      type: Transaction,
       args: {
         paymentHash: {
           type: GT.NonNull(PaymentHash),
diff --git a/core/api/test/bats/gql/invoice-for-wallet-by-payment-hash.gql b/core/api/test/bats/gql/invoice-for-wallet-by-payment-hash.gql
index aa90e4344b6..795a3fcc6ba 100644
--- a/core/api/test/bats/gql/invoice-for-wallet-by-payment-hash.gql
+++ b/core/api/test/bats/gql/invoice-for-wallet-by-payment-hash.gql
@@ -5,11 +5,9 @@ query me($walletId: WalletId!, $paymentHash: PaymentHash!) {
       walletById(walletId: $walletId) {
         id
         invoiceByPaymentHash(paymentHash: $paymentHash) {
+          paymentHash
           ... on LnInvoice {
-            paymentHash
-          }
-          ... on LnNoAmountInvoice {
-            paymentHash
+            satoshis
           }
         }
       }