diff --git a/cashu/nuts/nut04/nut04.go b/cashu/nuts/nut04/nut04.go
index 55557a9..a1632f7 100644
--- a/cashu/nuts/nut04/nut04.go
+++ b/cashu/nuts/nut04/nut04.go
@@ -3,7 +3,50 @@
 // [NUT-04]: https://github.com/cashubtc/nuts/blob/main/04.md
 package nut04
 
-import "github.com/elnosh/gonuts/cashu"
+import (
+	"encoding/json"
+
+	"github.com/elnosh/gonuts/cashu"
+)
+
+type State int
+
+const (
+	Unpaid State = iota
+	Paid
+	Pending
+	Issued
+	Unknown
+)
+
+func (state State) String() string {
+	switch state {
+	case Unpaid:
+		return "UNPAID"
+	case Paid:
+		return "PAID"
+	case Pending:
+		return "PENDING"
+	case Issued:
+		return "ISSUED"
+	default:
+		return "unknown"
+	}
+}
+
+func StringToState(state string) State {
+	switch state {
+	case "UNPAID":
+		return Unpaid
+	case "PAID":
+		return Paid
+	case "PENDING":
+		return Pending
+	case "ISSUED":
+		return Issued
+	}
+	return Unknown
+}
 
 type PostMintQuoteBolt11Request struct {
 	Amount uint64 `json:"amount"`
@@ -13,7 +56,8 @@ type PostMintQuoteBolt11Request struct {
 type PostMintQuoteBolt11Response struct {
 	Quote   string `json:"quote"`
 	Request string `json:"request"`
-	Paid    bool   `json:"paid"`
+	State   State  `json:"state"`
+	Paid    bool   `json:"paid"` // DEPRECATED: use State instead
 	Expiry  int64  `json:"expiry"`
 }
 
@@ -25,3 +69,39 @@ type PostMintBolt11Request struct {
 type PostMintBolt11Response struct {
 	Signatures cashu.BlindedSignatures `json:"signatures"`
 }
+
+type TempQuote struct {
+	Quote   string `json:"quote"`
+	Request string `json:"request"`
+	State   string `json:"state"`
+	Paid    bool   `json:"paid"` // DEPRECATED: use State instead
+	Expiry  int64  `json:"expiry"`
+}
+
+func (quoteResponse *PostMintQuoteBolt11Response) MarshalJSON() ([]byte, error) {
+	var tempQuote = TempQuote{
+		Quote:   quoteResponse.Quote,
+		Request: quoteResponse.Request,
+		State:   quoteResponse.State.String(),
+		Paid:    quoteResponse.Paid,
+		Expiry:  quoteResponse.Expiry,
+	}
+	return json.Marshal(tempQuote)
+}
+
+func (quoteResponse *PostMintQuoteBolt11Response) UnmarshalJSON(data []byte) error {
+	tempQuote := &TempQuote{}
+
+	if err := json.Unmarshal(data, tempQuote); err != nil {
+		return err
+	}
+
+	quoteResponse.Quote = tempQuote.Quote
+	quoteResponse.Request = tempQuote.Request
+	state := StringToState(tempQuote.State)
+	quoteResponse.State = state
+	quoteResponse.Paid = tempQuote.Paid
+	quoteResponse.Expiry = tempQuote.Expiry
+
+	return nil
+}
diff --git a/mint/mint.go b/mint/mint.go
index 15056ce..7d14916 100644
--- a/mint/mint.go
+++ b/mint/mint.go
@@ -119,7 +119,8 @@ func (m *Mint) RequestMintQuote(method string, amount uint64, unit string) (nut0
 	reqMintQuoteResponse := nut04.PostMintQuoteBolt11Response{
 		Quote:   invoice.Id,
 		Request: invoice.PaymentRequest,
-		Paid:    invoice.Settled,
+		State:   nut04.Unpaid,
+		Paid:    invoice.Settled, // DEPRECATED: remove after wallets have upgraded
 		Expiry:  invoice.Expiry,
 	}
 
@@ -144,15 +145,22 @@ func (m *Mint) GetMintQuoteState(method, quoteId string) (nut04.PostMintQuoteBol
 		msg := fmt.Sprintf("error getting invoice status: %v", err)
 		return nut04.PostMintQuoteBolt11Response{}, cashu.BuildCashuError(msg, cashu.InvoiceErrCode)
 	}
-	if status.Settled && status.Settled != invoice.Settled {
+
+	state := nut04.Unpaid
+	if status.Settled {
 		invoice.Settled = status.Settled
+		state = nut04.Paid
+		if invoice.Redeemed {
+			state = nut04.Issued
+		}
 		m.db.SaveInvoice(*invoice)
 	}
 
 	quoteState := nut04.PostMintQuoteBolt11Response{
 		Quote:   invoice.Id,
 		Request: invoice.PaymentRequest,
-		Paid:    invoice.Settled,
+		State:   state,
+		Paid:    invoice.Settled, // DEPRECATED: remove after wallets have upgraded
 		Expiry:  invoice.Expiry,
 	}
 	return quoteState, nil
diff --git a/mint/server.go b/mint/server.go
index eb4b079..372d1c7 100644
--- a/mint/server.go
+++ b/mint/server.go
@@ -219,7 +219,7 @@ func (ms *MintServer) mintRequest(rw http.ResponseWriter, req *http.Request) {
 		return
 	}
 
-	jsonRes, err := json.Marshal(reqMintResponse)
+	jsonRes, err := json.Marshal(&reqMintResponse)
 	if err != nil {
 		ms.writeErr(rw, req, cashu.StandardErr)
 		return
@@ -246,7 +246,7 @@ func (ms *MintServer) mintQuoteState(rw http.ResponseWriter, req *http.Request)
 		ms.writeErr(rw, req, err)
 		return
 	}
-	jsonRes, err := json.Marshal(mintQuoteStateResponse)
+	jsonRes, err := json.Marshal(&mintQuoteStateResponse)
 	if err != nil {
 		ms.writeErr(rw, req, cashu.StandardErr)
 		return
diff --git a/wallet/wallet.go b/wallet/wallet.go
index b2d9369..d1b680c 100644
--- a/wallet/wallet.go
+++ b/wallet/wallet.go
@@ -310,16 +310,6 @@ func (w *Wallet) RequestMint(amount uint64) (*nut04.PostMintQuoteBolt11Response,
 	return mintResponse, nil
 }
 
-// CheckQuotePaid reports whether the mint quote has been paid
-func (w *Wallet) CheckQuotePaid(quoteId string) bool {
-	mintQuote, err := GetMintQuoteState(w.currentMint.mintURL, quoteId)
-	if err != nil {
-		return false
-	}
-
-	return mintQuote.Paid
-}
-
 // MintTokens will check whether if the mint quote has been paid.
 // If yes, it will create blinded messages that will send to the mint
 // to get the blinded signatures.
@@ -330,7 +320,8 @@ func (w *Wallet) MintTokens(quoteId string) (cashu.Proofs, error) {
 	if err != nil {
 		return nil, err
 	}
-	if !mintQuote.Paid {
+	// TODO: remove usage of 'Paid' field after mints have upgraded
+	if !mintQuote.Paid || mintQuote.State == nut04.Unpaid {
 		return nil, errors.New("invoice not paid")
 	}