diff --git a/VoiceInk/Models/PredefinedModels.swift b/VoiceInk/Models/PredefinedModels.swift
index 2fee46d..9fb28f0 100644
--- a/VoiceInk/Models/PredefinedModels.swift
+++ b/VoiceInk/Models/PredefinedModels.swift
@@ -265,6 +265,17 @@ import Foundation
             isMultilingual: true,
             supportedLanguages: getLanguageDictionary(isMultilingual: true, provider: .gemini)
         )
+        ,
+        CloudModel(
+            name: "stt-async-v3",
+            displayName: "Soniox (stt-async-v3)",
+            description: "Soniox asynchronous transcription model v3.",
+            provider: .soniox,
+            speed: 0.8,
+            accuracy: 0.96,
+            isMultilingual: true,
+            supportedLanguages: getLanguageDictionary(isMultilingual: true, provider: .soniox)
+        )
      ]
  
      static let allLanguages = [
diff --git a/VoiceInk/Models/TranscriptionModel.swift b/VoiceInk/Models/TranscriptionModel.swift
index 8d308ee..2617682 100644
--- a/VoiceInk/Models/TranscriptionModel.swift
+++ b/VoiceInk/Models/TranscriptionModel.swift
@@ -9,6 +9,7 @@ enum ModelProvider: String, Codable, Hashable, CaseIterable {
     case deepgram = "Deepgram"
     case mistral = "Mistral"
     case gemini = "Gemini"
+    case soniox = "Soniox"
     case custom = "Custom"
     case nativeApple = "Native Apple"
     // Future providers can be added here
diff --git a/VoiceInk/Services/AIService.swift b/VoiceInk/Services/AIService.swift
index 1fd8eb3..d4a1a87 100644
--- a/VoiceInk/Services/AIService.swift
+++ b/VoiceInk/Services/AIService.swift
@@ -11,6 +11,7 @@ enum AIProvider: String, CaseIterable {
     case mistral = "Mistral"
     case elevenLabs = "ElevenLabs"
     case deepgram = "Deepgram"
+    case soniox = "Soniox"
     case ollama = "Ollama"
     case custom = "Custom"
     
@@ -35,6 +36,8 @@ enum AIProvider: String, CaseIterable {
             return "https://api.elevenlabs.io/v1/speech-to-text"
         case .deepgram:
             return "https://api.deepgram.com/v1/listen"
+        case .soniox:
+            return "https://api.soniox.com/v1"
         case .ollama:
             return UserDefaults.standard.string(forKey: "ollamaBaseURL") ?? "http://localhost:11434"
         case .custom:
@@ -60,6 +63,8 @@ enum AIProvider: String, CaseIterable {
             return "scribe_v1"
         case .deepgram:
             return "whisper-1"
+        case .soniox:
+            return "stt-async-v3"
         case .ollama:
             return UserDefaults.standard.string(forKey: "ollamaSelectedModel") ?? "mistral"
         case .custom:
@@ -122,6 +127,8 @@ enum AIProvider: String, CaseIterable {
             return ["scribe_v1", "scribe_v1_experimental"]
         case .deepgram:
             return ["whisper-1"]
+        case .soniox:
+            return ["stt-async-v3"]
         case .ollama:
             return []
         case .custom:
@@ -308,6 +315,8 @@ class AIService: ObservableObject {
             verifyDeepgramAPIKey(key, completion: completion)
         case .mistral:
             verifyMistralAPIKey(key, completion: completion)
+        case .soniox:
+            verifySonioxAPIKey(key, completion: completion)
         default:
             verifyOpenAICompatibleAPIKey(key, completion: completion)
         }
@@ -462,6 +471,31 @@ class AIService: ObservableObject {
         }.resume()
     }
     
+    private func verifySonioxAPIKey(_ key: String, completion: @escaping (Bool) -> Void) {
+        guard let url = URL(string: "https://api.soniox.com/v1/files") else {
+            completion(false)
+            return
+        }
+        var request = URLRequest(url: url)
+        request.httpMethod = "GET"
+        request.addValue("Bearer \(key)", forHTTPHeaderField: "Authorization")
+        request.addValue("application/json", forHTTPHeaderField: "Accept")
+        
+        URLSession.shared.dataTask(with: request) { _, response, error in
+            if let error = error {
+                self.logger.error("Soniox API key verification failed: \(error.localizedDescription)")
+                completion(false)
+                return
+            }
+            
+            if let httpResponse = response as? HTTPURLResponse {
+                completion(httpResponse.statusCode == 200)
+            } else {
+                completion(false)
+            }
+        }.resume()
+    }
+    
     func clearAPIKey() {
         guard selectedProvider.requiresAPIKey else { return }
         
diff --git a/VoiceInk/Services/CloudTranscription/CloudTranscriptionService.swift b/VoiceInk/Services/CloudTranscription/CloudTranscriptionService.swift
index f7037c3..75af540 100644
--- a/VoiceInk/Services/CloudTranscription/CloudTranscriptionService.swift
+++ b/VoiceInk/Services/CloudTranscription/CloudTranscriptionService.swift
@@ -41,6 +41,7 @@ class CloudTranscriptionService: TranscriptionService {
     private lazy var mistralService = MistralTranscriptionService()
     private lazy var geminiService = GeminiTranscriptionService()
     private lazy var openAICompatibleService = OpenAICompatibleTranscriptionService()
+    private lazy var sonioxService = SonioxTranscriptionService()
     
     func transcribe(audioURL: URL, model: any TranscriptionModel) async throws -> String {
         var text: String
@@ -56,6 +57,8 @@ class CloudTranscriptionService: TranscriptionService {
             text = try await mistralService.transcribe(audioURL: audioURL, model: model)
         case .gemini:
             text = try await geminiService.transcribe(audioURL: audioURL, model: model)
+        case .soniox:
+            text = try await sonioxService.transcribe(audioURL: audioURL, model: model)
         case .custom:
             guard let customModel = model as? CustomCloudModel else {
                 throw CloudTranscriptionError.unsupportedProvider
diff --git a/VoiceInk/Services/CloudTranscription/SonioxTranscriptionService.swift b/VoiceInk/Services/CloudTranscription/SonioxTranscriptionService.swift
new file mode 100644
index 0000000..4eac4f4
--- /dev/null
+++ b/VoiceInk/Services/CloudTranscription/SonioxTranscriptionService.swift
@@ -0,0 +1,201 @@
+import Foundation
+
+class SonioxTranscriptionService {
+    private let apiBase = "https://api.soniox.com/v1"
+    
+    func transcribe(audioURL: URL, model: any TranscriptionModel) async throws -> String {
+        let config = try getAPIConfig(for: model)
+        
+        let fileId = try await uploadFile(audioURL: audioURL, apiKey: config.apiKey)
+        let transcriptionId = try await createTranscription(fileId: fileId, apiKey: config.apiKey, modelName: model.name)
+        try await pollTranscriptionStatus(id: transcriptionId, apiKey: config.apiKey)
+        let transcript = try await fetchTranscript(id: transcriptionId, apiKey: config.apiKey)
+        
+        guard !transcript.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty else {
+            throw CloudTranscriptionError.noTranscriptionReturned
+        }
+        return transcript
+    }
+    
+    private func getAPIConfig(for model: any TranscriptionModel) throws -> APIConfig {
+        guard let apiKey = UserDefaults.standard.string(forKey: "SonioxAPIKey"), !apiKey.isEmpty else {
+            throw CloudTranscriptionError.missingAPIKey
+        }
+        return APIConfig(apiKey: apiKey)
+    }
+    
+    private func uploadFile(audioURL: URL, apiKey: String) async throws -> String {
+        guard let apiURL = URL(string: "\(apiBase)/files") else {
+            throw CloudTranscriptionError.dataEncodingError
+        }
+        var request = URLRequest(url: apiURL)
+        request.httpMethod = "POST"
+        request.setValue("Bearer \(apiKey)", forHTTPHeaderField: "Authorization")
+        let boundary = "Boundary-\(UUID().uuidString)"
+        request.setValue("multipart/form-data; boundary=\(boundary)", forHTTPHeaderField: "Content-Type")
+        let body = try createMultipartBody(fileURL: audioURL, boundary: boundary)
+        let (data, response) = try await URLSession.shared.upload(for: request, from: body)
+        guard let httpResponse = response as? HTTPURLResponse else {
+            throw CloudTranscriptionError.networkError(URLError(.badServerResponse))
+        }
+        if !(200...299).contains(httpResponse.statusCode) {
+            let errorMessage = String(data: data, encoding: .utf8) ?? "No error message"
+            throw CloudTranscriptionError.apiRequestFailed(statusCode: httpResponse.statusCode, message: errorMessage)
+        }
+        do {
+            let uploadResponse = try JSONDecoder().decode(FileUploadResponse.self, from: data)
+            return uploadResponse.id
+        } catch {
+            throw CloudTranscriptionError.noTranscriptionReturned
+        }
+    }
+    
+    private func createTranscription(fileId: String, apiKey: String, modelName: String) async throws -> String {
+        guard let apiURL = URL(string: "\(apiBase)/transcriptions") else {
+            throw CloudTranscriptionError.dataEncodingError
+        }
+        var request = URLRequest(url: apiURL)
+        request.httpMethod = "POST"
+        request.setValue("Bearer \(apiKey)", forHTTPHeaderField: "Authorization")
+        request.setValue("application/json", forHTTPHeaderField: "Content-Type")
+        var payload: [String: Any] = [
+            "file_id": fileId,
+            "model": modelName,
+            // Disable diarization as per app requirement
+            "enable_speaker_diarization": false
+        ]
+        // Attach custom vocabulary terms from the app's dictionary (if any)
+        let dictionaryTerms = getCustomDictionaryTerms()
+        if !dictionaryTerms.isEmpty {
+            payload["context"] = [
+                "terms": dictionaryTerms
+            ]
+        }
+        let selectedLanguage = UserDefaults.standard.string(forKey: "SelectedLanguage") ?? "auto"
+        if selectedLanguage != "auto" && !selectedLanguage.isEmpty {
+            payload["language_hints"] = [selectedLanguage]
+        }
+        request.httpBody = try JSONSerialization.data(withJSONObject: payload)
+        let (data, response) = try await URLSession.shared.data(for: request)
+        guard let httpResponse = response as? HTTPURLResponse else {
+            throw CloudTranscriptionError.networkError(URLError(.badServerResponse))
+        }
+        if !(200...299).contains(httpResponse.statusCode) {
+            let errorMessage = String(data: data, encoding: .utf8) ?? "No error message"
+            throw CloudTranscriptionError.apiRequestFailed(statusCode: httpResponse.statusCode, message: errorMessage)
+        }
+        do {
+            let createResponse = try JSONDecoder().decode(CreateTranscriptionResponse.self, from: data)
+            return createResponse.id
+        } catch {
+            throw CloudTranscriptionError.noTranscriptionReturned
+        }
+    }
+    
+    private func pollTranscriptionStatus(id: String, apiKey: String) async throws {
+        guard let baseURL = URL(string: "\(apiBase)/transcriptions/\(id)") else {
+            throw CloudTranscriptionError.dataEncodingError
+        }
+        let start = Date()
+        let maxWaitSeconds: TimeInterval = 300
+        while true {
+            var request = URLRequest(url: baseURL)
+            request.httpMethod = "GET"
+            request.setValue("Bearer \(apiKey)", forHTTPHeaderField: "Authorization")
+            let (data, response) = try await URLSession.shared.data(for: request)
+            guard let httpResponse = response as? HTTPURLResponse else {
+                throw CloudTranscriptionError.networkError(URLError(.badServerResponse))
+            }
+            if !(200...299).contains(httpResponse.statusCode) {
+                let errorMessage = String(data: data, encoding: .utf8) ?? "No error message"
+                throw CloudTranscriptionError.apiRequestFailed(statusCode: httpResponse.statusCode, message: errorMessage)
+            }
+            do {
+                let status = try JSONDecoder().decode(TranscriptionStatusResponse.self, from: data)
+                switch status.status.lowercased() {
+                case "completed":
+                    return
+                case "failed":
+                    throw CloudTranscriptionError.apiRequestFailed(statusCode: 500, message: "Transcription failed")
+                default:
+                    break
+                }
+            } catch {
+                // Decoding status failed, will retry
+            }
+            if Date().timeIntervalSince(start) > maxWaitSeconds {
+                throw CloudTranscriptionError.apiRequestFailed(statusCode: 504, message: "Transcription timed out")
+            }
+            try await Task.sleep(nanoseconds: 1_000_000_000)
+        }
+    }
+    
+    private func fetchTranscript(id: String, apiKey: String) async throws -> String {
+        guard let apiURL = URL(string: "\(apiBase)/transcriptions/\(id)/transcript") else {
+            throw CloudTranscriptionError.dataEncodingError
+        }
+        var request = URLRequest(url: apiURL)
+        request.httpMethod = "GET"
+        request.setValue("Bearer \(apiKey)", forHTTPHeaderField: "Authorization")
+        let (data, response) = try await URLSession.shared.data(for: request)
+        guard let httpResponse = response as? HTTPURLResponse else {
+            throw CloudTranscriptionError.networkError(URLError(.badServerResponse))
+        }
+        if !(200...299).contains(httpResponse.statusCode) {
+            let errorMessage = String(data: data, encoding: .utf8) ?? "No error message"
+            throw CloudTranscriptionError.apiRequestFailed(statusCode: httpResponse.statusCode, message: errorMessage)
+        }
+        if let decoded = try? JSONDecoder().decode(TranscriptResponse.self, from: data) {
+            return decoded.text
+        }
+        if let asString = String(data: data, encoding: .utf8), !asString.isEmpty {
+            return asString
+        }
+        throw CloudTranscriptionError.noTranscriptionReturned
+    }
+    
+    private func createMultipartBody(fileURL: URL, boundary: String) throws -> Data {
+        var body = Data()
+        let crlf = "\r\n"
+        guard let audioData = try? Data(contentsOf: fileURL) else {
+            throw CloudTranscriptionError.audioFileNotFound
+        }
+        body.append("--\(boundary)\(crlf)".data(using: .utf8)!)
+        body.append("Content-Disposition: form-data; name=\"file\"; filename=\"\(fileURL.lastPathComponent)\"\(crlf)".data(using: .utf8)!)
+        body.append("Content-Type: audio/wav\(crlf)\(crlf)".data(using: .utf8)!)
+        body.append(audioData)
+        body.append(crlf.data(using: .utf8)!)
+        body.append("--\(boundary)--\(crlf)".data(using: .utf8)!)
+        return body
+    }
+    
+    private func getCustomDictionaryTerms() -> [String] {
+        guard let data = UserDefaults.standard.data(forKey: "CustomDictionaryItems") else {
+            return []
+        }
+        // Decode without depending on UI layer types; extract "word" strings
+        guard let json = try? JSONSerialization.jsonObject(with: data) as? [[String: Any]] else {
+            return []
+        }
+        let words = json.compactMap { $0["word"] as? String }
+            .map { $0.trimmingCharacters(in: .whitespacesAndNewlines) }
+            .filter { !$0.isEmpty }
+        // De-duplicate while preserving order
+        var seen = Set<String>()
+        var unique: [String] = []
+        for w in words {
+            let key = w.lowercased()
+            if !seen.contains(key) {
+                seen.insert(key)
+                unique.append(w)
+            }
+        }
+        return unique
+    }
+    
+    private struct APIConfig { let apiKey: String }
+    private struct FileUploadResponse: Decodable { let id: String }
+    private struct CreateTranscriptionResponse: Decodable { let id: String }
+    private struct TranscriptionStatusResponse: Decodable { let status: String }
+    private struct TranscriptResponse: Decodable { let text: String }
+}
diff --git a/VoiceInk/Views/AI Models/APIKeyManagementView.swift b/VoiceInk/Views/AI Models/APIKeyManagementView.swift
index e36dd01..45df228 100644
--- a/VoiceInk/Views/AI Models/APIKeyManagementView.swift	
+++ b/VoiceInk/Views/AI Models/APIKeyManagementView.swift	
@@ -17,7 +17,7 @@ struct APIKeyManagementView: View {
             // Provider Selection
             HStack {
                 Picker("AI Provider", selection: $aiService.selectedProvider) {
-                    ForEach(AIProvider.allCases.filter { $0 != .elevenLabs && $0 != .deepgram }, id: \.self) { provider in
+                    ForEach(AIProvider.allCases.filter { $0 != .elevenLabs && $0 != .deepgram && $0 != .soniox }, id: \.self) { provider in
                         Text(provider.rawValue).tag(provider)
                     }
                 }
@@ -411,6 +411,8 @@ struct APIKeyManagementView: View {
                                             URL(string: "https://elevenlabs.io/speech-synthesis")!
                                         case .deepgram:
                                             URL(string: "https://console.deepgram.com/api-keys")!
+                                            case .soniox:
+                                                URL(string: "https://console.soniox.com/")!
                                         case .ollama, .custom:
                                             URL(string: "")! // This case should never be reached
                                         case .openRouter:
diff --git a/VoiceInk/Views/AI Models/CloudModelCardRowView.swift b/VoiceInk/Views/AI Models/CloudModelCardRowView.swift
index 04fc2f8..d00cc1a 100644
--- a/VoiceInk/Views/AI Models/CloudModelCardRowView.swift	
+++ b/VoiceInk/Views/AI Models/CloudModelCardRowView.swift	
@@ -38,6 +38,8 @@ struct CloudModelCardView: View {
             return "Mistral"
         case .gemini:
             return "Gemini"
+        case .soniox:
+            return "Soniox"
         default:
             return model.provider.rawValue
         }
@@ -281,6 +283,8 @@ struct CloudModelCardView: View {
             aiService.selectedProvider = .mistral
         case .gemini:
             aiService.selectedProvider = .gemini
+        case .soniox:
+            aiService.selectedProvider = .soniox
         default:
             // This case should ideally not be hit for cloud models in this view
             print("Warning: verifyAPIKey called for unsupported provider \(model.provider.rawValue)")
diff --git a/VoiceInk/Views/AI Models/ModelCardRowView.swift b/VoiceInk/Views/AI Models/ModelCardRowView.swift
index 012a750..c63d8c1 100644
--- a/VoiceInk/Views/AI Models/ModelCardRowView.swift	
+++ b/VoiceInk/Views/AI Models/ModelCardRowView.swift	
@@ -56,7 +56,7 @@ struct ModelCardRowView: View {
                         setDefaultAction: setDefaultAction
                     )
                 }
-            case .groq, .elevenLabs, .deepgram, .mistral, .gemini:
+            case .groq, .elevenLabs, .deepgram, .mistral, .gemini, .soniox:
                 if let cloudModel = model as? CloudModel {
                     CloudModelCardView(
                         model: cloudModel,
diff --git a/VoiceInk/Views/AI Models/ModelManagementView.swift b/VoiceInk/Views/AI Models/ModelManagementView.swift
index 3e1cbe4..001f80e 100644
--- a/VoiceInk/Views/AI Models/ModelManagementView.swift	
+++ b/VoiceInk/Views/AI Models/ModelManagementView.swift	
@@ -224,7 +224,7 @@ struct ModelManagementView: View {
         case .local:
             return whisperState.allAvailableModels.filter { $0.provider == .local || $0.provider == .nativeApple || $0.provider == .parakeet }
         case .cloud:
-            let cloudProviders: [ModelProvider] = [.groq, .elevenLabs, .deepgram, .mistral, .gemini]
+            let cloudProviders: [ModelProvider] = [.groq, .elevenLabs, .deepgram, .mistral, .gemini, .soniox]
             return whisperState.allAvailableModels.filter { cloudProviders.contains($0.provider) }
         case .custom:
             return whisperState.allAvailableModels.filter { $0.provider == .custom }
diff --git a/VoiceInk/Whisper/WhisperState+ModelQueries.swift b/VoiceInk/Whisper/WhisperState+ModelQueries.swift
index 5c76b0e..f634ea0 100644
--- a/VoiceInk/Whisper/WhisperState+ModelQueries.swift
+++ b/VoiceInk/Whisper/WhisperState+ModelQueries.swift
@@ -29,6 +29,9 @@ extension WhisperState {
             case .gemini:
                 let key = UserDefaults.standard.string(forKey: "GeminiAPIKey")
                 return key != nil && !key!.isEmpty
+            case .soniox:
+                let key = UserDefaults.standard.string(forKey: "SonioxAPIKey")
+                return key != nil && !key!.isEmpty
             case .custom:
                 // Custom models are always usable since they contain their own API keys
                 return true