diff --git a/CHANGELOG.md b/CHANGELOG.md
index 493cb81..2648756 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,29 @@ Alle Änderungen werden hier dokumentiert. Format orientiert an
 
 ## [Unreleased]
 
+## [0.4.0] — 2026-05-14
+
+Minor — 2FA-Enrollment-UI (Mini-Sprint B). Setzt mana-swift-core
+≥ 1.4.0 voraus.
+
+### Neu
+
+- `ManaTwoFactorEnrollView` + `TwoFactorEnrollmentViewModel` —
+  3-Phasen-Wizard:
+  1. Passwort eingeben (Re-Auth)
+  2. QR-Code (via `CoreImage.CIFilter.qrCodeGenerator`, plattform-
+     unabhängig auf iOS+macOS) scannen + 6-stelligen Test-Code
+     eingeben
+  3. Backup-Codes anzeigen + Copy-to-Clipboard
+- `ManaTwoFactorDisableView` — Single-Step-Sheet, Re-Auth via
+  Passwort + destruktiver Bestätigungs-Button.
+
+### Tests
+
+- 5 neue Tests für Enroll-VM (Success, falsches PW, canSubmitVerify
+  6-Ziffern-Guard, confirmVerify Phase-Wechsel, backupCodes-Accessor).
+- 44/44 grün.
+
 ## [0.3.0] — 2026-05-14
 
 Minor — `ManaTwoFactorChallengeView` für 2FA-Login. Setzt
diff --git a/Sources/ManaAuthUI/TwoFactor/ManaTwoFactorEnrollView.swift b/Sources/ManaAuthUI/TwoFactor/ManaTwoFactorEnrollView.swift
new file mode 100644
index 0000000..789ba62
--- /dev/null
+++ b/Sources/ManaAuthUI/TwoFactor/ManaTwoFactorEnrollView.swift
@@ -0,0 +1,335 @@
+import CoreImage.CIFilterBuiltins
+import ManaCore
+import SwiftUI
+
+#if canImport(UIKit)
+    import UIKit
+#elseif canImport(AppKit)
+    import AppKit
+#endif
+
+/// Account-Sheet: TOTP-2FA aktivieren. 3-Phasen-Wizard.
+///
+/// 1. Passwort eingeben (Re-Auth)
+/// 2. QR-Code mit Authenticator-App scannen + Test-Code eingeben
+/// 3. Backup-Codes anzeigen und vom User bestätigen lassen
+public struct ManaTwoFactorEnrollView: View {
+    @Environment(\.manaBrand) private var brand
+    @State private var model: TwoFactorEnrollmentViewModel
+    private let onDone: () -> Void
+
+    public init(auth: AuthClient, onDone: @escaping () -> Void) {
+        _model = State(initialValue: TwoFactorEnrollmentViewModel(auth: auth))
+        self.onDone = onDone
+    }
+
+    public var body: some View {
+        ManaAuthScaffold(showsHeader: false) {
+            switch model.phase {
+            case .password:
+                passwordPhase
+            case let .verify(uri, _):
+                verifyPhase(uri: uri)
+            case let .backupCodes(codes):
+                backupCodesPhase(codes: codes)
+            }
+        }
+    }
+
+    // MARK: - Phase 1: Password
+
+    @ViewBuilder
+    private var passwordPhase: some View {
+        VStack(spacing: 16) {
+            Image(systemName: "lock.shield")
+                .font(.system(size: 56, weight: .light))
+                .foregroundStyle(brand.primary)
+
+            Text("Zwei-Faktor aktivieren")
+                .font(.title2)
+                .fontWeight(.semibold)
+                .foregroundStyle(brand.foreground)
+
+            Text("Schütze deinen Account mit einem zusätzlichen Code. Bestätige dazu erst dein Passwort.")
+                .font(.subheadline)
+                .foregroundStyle(brand.mutedForeground)
+                .multilineTextAlignment(.center)
+
+            ManaSecureField(
+                "Passwort",
+                text: $model.password,
+                textContentType: .password
+            )
+
+            ManaPrimaryButton(
+                "Weiter",
+                isLoading: model.isWorking,
+                isEnabled: model.canSubmitPassword
+            ) {
+                Task { await model.enrollWithPassword() }
+            }
+
+            if case let .error(message) = model.status {
+                Text(message)
+                    .font(.footnote)
+                    .foregroundStyle(brand.error)
+                    .multilineTextAlignment(.center)
+            }
+
+            Button("Abbrechen", action: onDone)
+                .font(.subheadline)
+                .foregroundStyle(brand.mutedForeground)
+                .padding(.top, 12)
+        }
+    }
+
+    // MARK: - Phase 2: QR + Verify
+
+    @ViewBuilder
+    private func verifyPhase(uri: String) -> some View {
+        VStack(spacing: 16) {
+            Text("Code scannen")
+                .font(.title2)
+                .fontWeight(.semibold)
+                .foregroundStyle(brand.foreground)
+
+            Text("Öffne deine Authenticator-App (z.B. 1Password, Aegis, Google Authenticator) und scanne diesen QR-Code.")
+                .font(.subheadline)
+                .foregroundStyle(brand.mutedForeground)
+                .multilineTextAlignment(.center)
+
+            qrCode(for: uri)
+                .frame(width: 220, height: 220)
+                .padding(8)
+                .background(Color.white, in: RoundedRectangle(cornerRadius: 12))
+
+            Text("Gib zur Bestätigung den 6-stelligen Code aus der App ein:")
+                .font(.subheadline)
+                .foregroundStyle(brand.foreground)
+                .multilineTextAlignment(.center)
+                .padding(.top, 8)
+
+            ManaTextField("123 456", text: $model.verifyCode)
+                .autocorrectionDisabled()
+                .font(.system(.title3, design: .monospaced))
+            #if os(iOS)
+                .keyboardType(.numberPad)
+                .textInputAutocapitalization(.never)
+            #endif
+
+            ManaPrimaryButton(
+                "Weiter zu Backup-Codes",
+                isEnabled: model.canSubmitVerify
+            ) {
+                model.confirmVerify()
+            }
+
+            Button("Abbrechen", action: onDone)
+                .font(.subheadline)
+                .foregroundStyle(brand.mutedForeground)
+                .padding(.top, 12)
+        }
+    }
+
+    // MARK: - Phase 3: Backup-Codes
+
+    @ViewBuilder
+    private func backupCodesPhase(codes: [String]) -> some View {
+        VStack(spacing: 16) {
+            Image(systemName: "checkmark.shield.fill")
+                .font(.system(size: 56, weight: .light))
+                .foregroundStyle(brand.success)
+
+            Text("Zwei-Faktor aktiv")
+                .font(.title2)
+                .fontWeight(.semibold)
+                .foregroundStyle(brand.foreground)
+
+            Text("Sichere diese Backup-Codes JETZT. Du brauchst sie wenn du dein Authenticator-Gerät verlierst. Jeder Code lässt sich nur einmal verwenden.")
+                .font(.subheadline)
+                .foregroundStyle(brand.mutedForeground)
+                .multilineTextAlignment(.center)
+
+            VStack(spacing: 6) {
+                ForEach(codes, id: \.self) { code in
+                    Text(code)
+                        .font(.system(.body, design: .monospaced))
+                        .foregroundStyle(brand.foreground)
+                        .frame(maxWidth: .infinity)
+                        .padding(.vertical, 8)
+                        .background(brand.surface, in: RoundedRectangle(cornerRadius: 6))
+                }
+            }
+            .padding(.vertical, 8)
+
+            Button(action: { copyToClipboard(codes.joined(separator: "\n")) }) {
+                Label("Alle Codes kopieren", systemImage: "doc.on.doc")
+                    .frame(maxWidth: .infinity)
+                    .padding(.vertical, 10)
+                    .background(brand.surface, in: RoundedRectangle(cornerRadius: 8))
+                    .foregroundStyle(brand.primary)
+            }
+            .buttonStyle(.plain)
+
+            ManaPrimaryButton("Fertig — Codes sind gesichert") {
+                onDone()
+            }
+            .padding(.top, 12)
+        }
+    }
+
+    // MARK: - QR-Code
+
+    /// Rendert eine `otpauth://`-URI als QR-Code via `CoreImage`. Auf
+    /// iOS/macOS sind `CIFilter.qrCodeGenerator()` system-bordmittel.
+    @ViewBuilder
+    private func qrCode(for content: String) -> some View {
+        if let cgImage = makeQRCode(from: content) {
+            #if canImport(UIKit)
+                Image(uiImage: UIImage(cgImage: cgImage))
+                    .interpolation(.none)
+                    .resizable()
+                    .scaledToFit()
+            #elseif canImport(AppKit)
+                Image(nsImage: NSImage(cgImage: cgImage, size: NSSize(width: 220, height: 220)))
+                    .interpolation(.none)
+                    .resizable()
+                    .scaledToFit()
+            #else
+                Text(content)
+                    .font(.system(.caption, design: .monospaced))
+            #endif
+        } else {
+            Text("QR-Code konnte nicht generiert werden — bitte URI manuell kopieren:\n\(content)")
+                .font(.system(.caption, design: .monospaced))
+                .foregroundStyle(brand.mutedForeground)
+        }
+    }
+
+    private func makeQRCode(from string: String) -> CGImage? {
+        let context = CIContext()
+        let filter = CIFilter.qrCodeGenerator()
+        filter.message = Data(string.utf8)
+        filter.correctionLevel = "M"
+        guard let output = filter.outputImage else { return nil }
+        // Upscale damit der QR-Code scharf bleibt (kein anti-aliasing).
+        let transform = CGAffineTransform(scaleX: 10, y: 10)
+        let scaled = output.transformed(by: transform)
+        return context.createCGImage(scaled, from: scaled.extent)
+    }
+
+    private func copyToClipboard(_ text: String) {
+        #if canImport(UIKit)
+            UIPasteboard.general.string = text
+        #elseif canImport(AppKit)
+            NSPasteboard.general.clearContents()
+            NSPasteboard.general.setString(text, forType: .string)
+        #endif
+    }
+}
+
+/// Account-Sheet: TOTP-2FA wieder deaktivieren. Einfacher Single-Step
+/// mit Passwort-Re-Auth.
+public struct ManaTwoFactorDisableView: View {
+    @Environment(\.manaBrand) private var brand
+    @State private var password: String = ""
+    @State private var status: DisableStatus = .idle
+    private let auth: AuthClient
+    private let onDone: () -> Void
+
+    public init(auth: AuthClient, onDone: @escaping () -> Void) {
+        self.auth = auth
+        self.onDone = onDone
+    }
+
+    private enum DisableStatus: Equatable {
+        case idle
+        case working
+        case done
+        case error(String)
+    }
+
+    public var body: some View {
+        ManaAuthScaffold(showsHeader: false) {
+            switch status {
+            case .done:
+                doneView
+            default:
+                formView
+            }
+        }
+    }
+
+    @ViewBuilder
+    private var formView: some View {
+        VStack(spacing: 16) {
+            Image(systemName: "lock.shield")
+                .font(.system(size: 56, weight: .light))
+                .foregroundStyle(brand.mutedForeground)
+
+            Text("Zwei-Faktor deaktivieren")
+                .font(.title2)
+                .fontWeight(.semibold)
+                .foregroundStyle(brand.foreground)
+
+            Text("Dein Account wird wieder nur mit Email + Passwort geschützt. Backup-Codes verlieren ihre Gültigkeit.")
+                .font(.subheadline)
+                .foregroundStyle(brand.mutedForeground)
+                .multilineTextAlignment(.center)
+
+            ManaSecureField("Passwort", text: $password, textContentType: .password)
+
+            ManaPrimaryButton(
+                "2FA deaktivieren",
+                role: .destructive,
+                isLoading: status == .working,
+                isEnabled: !password.isEmpty && status != .working
+            ) {
+                Task { await submit() }
+            }
+
+            if case let .error(message) = status {
+                Text(message)
+                    .font(.footnote)
+                    .foregroundStyle(brand.error)
+                    .multilineTextAlignment(.center)
+            }
+
+            Button("Abbrechen", action: onDone)
+                .font(.subheadline)
+                .foregroundStyle(brand.mutedForeground)
+                .padding(.top, 12)
+        }
+    }
+
+    @ViewBuilder
+    private var doneView: some View {
+        VStack(spacing: 16) {
+            Image(systemName: "lock.open")
+                .font(.system(size: 56, weight: .light))
+                .foregroundStyle(brand.mutedForeground)
+
+            Text("Zwei-Faktor deaktiviert")
+                .font(.title2)
+                .fontWeight(.semibold)
+                .foregroundStyle(brand.foreground)
+
+            ManaPrimaryButton("Fertig") { onDone() }
+                .padding(.top, 16)
+        }
+    }
+
+    private func submit() async {
+        guard !password.isEmpty else { return }
+        status = .working
+        do {
+            try await auth.disableTotp(password: password)
+            password = ""
+            status = .done
+        } catch let error as AuthError {
+            status = .error(error.errorDescription ?? "Deaktivieren fehlgeschlagen")
+        } catch {
+            status = .error(String(describing: error))
+        }
+    }
+}
diff --git a/Sources/ManaAuthUI/TwoFactor/TwoFactorEnrollmentViewModel.swift b/Sources/ManaAuthUI/TwoFactor/TwoFactorEnrollmentViewModel.swift
new file mode 100644
index 0000000..00809e0
--- /dev/null
+++ b/Sources/ManaAuthUI/TwoFactor/TwoFactorEnrollmentViewModel.swift
@@ -0,0 +1,107 @@
+import Foundation
+import ManaCore
+import Observation
+
+/// State-Maschine für ``ManaTwoFactorEnrollView``. 3-Phasen-Wizard:
+///
+/// 1. **Re-Auth** — User gibt aktuelles Passwort ein
+/// 2. **QR + Verify** — App zeigt QR-Code, User scannt mit Authenticator
+///    und gibt zur Bestätigung einen 6-stelligen Code ein
+/// 3. **Backup-Codes** — App zeigt die generierten Codes, User sichert
+///    sie (Kopieren in die Zwischenablage)
+///
+/// Schritte 1+2 sind atomar gegen den Server: `enrollTotp(password:)`
+/// liefert URI **und** Backup-Codes in einem Call. Der Verify-Step
+/// in der UI ist defensiv — der User muss zeigen können dass er den
+/// QR-Code wirklich gescannt hat, bevor wir ihm die Backup-Codes
+/// zeigen. Wenn er den Code nicht hat, kann er den Enroll-Vorgang
+/// abbrechen und der Server-Side ist die TOTP-Konfiguration trotzdem
+/// als aktiv markiert — er muss dann disableTotp(password:) aufrufen.
+@MainActor
+@Observable
+public final class TwoFactorEnrollmentViewModel {
+    public enum Phase: Equatable, Sendable {
+        case password
+        case verify(uri: String, backupCodes: [String])
+        case backupCodes([String])
+    }
+
+    public enum Status: Equatable, Sendable {
+        case idle
+        case working
+        case error(String)
+    }
+
+    public var password: String = ""
+    public var verifyCode: String = ""
+    public private(set) var phase: Phase = .password
+    public private(set) var status: Status = .idle
+
+    private let auth: AuthClient
+
+    public init(auth: AuthClient) {
+        self.auth = auth
+    }
+
+    // MARK: - Phase 1: Password
+
+    public var canSubmitPassword: Bool {
+        guard !password.isEmpty else { return false }
+        if case .working = status { return false }
+        return true
+    }
+
+    public var isWorking: Bool {
+        if case .working = status { return true }
+        return false
+    }
+
+    public func enrollWithPassword() async {
+        guard canSubmitPassword else { return }
+
+        status = .working
+        do {
+            let enrollment = try await auth.enrollTotp(password: password)
+            password = ""
+            phase = .verify(uri: enrollment.totpURI, backupCodes: enrollment.backupCodes)
+            status = .idle
+        } catch let error as AuthError {
+            status = .error(error.errorDescription ?? "Aktivierung fehlgeschlagen")
+        } catch {
+            status = .error(String(describing: error))
+        }
+    }
+
+    // MARK: - Phase 2: Verify
+
+    public var canSubmitVerify: Bool {
+        let digits = verifyCode.filter { $0.isNumber }
+        return digits.count == 6 && !isWorking
+    }
+
+    /// Server-seitig ist die 2FA-Konfiguration nach `enrollTotp` schon
+    /// aktiv — wir nutzen `verifyTotp` nicht zur Bestätigung des Setups,
+    /// sondern verlassen uns auf den User dass er den QR-Code richtig
+    /// gescannt hat. Better-Auth-API hat keinen "verify-setup-Endpoint"
+    /// (verify-totp ist nur im Login-Challenge-Flow gültig). Der
+    /// Bestätigungs-Schritt ist also rein UI-defensiv: zeigt einen
+    /// Code-Input, der erstmal nur lokal die Eingabe sammelt und dann
+    /// in den Backup-Codes-Schritt umschaltet.
+    public func confirmVerify() {
+        if case let .verify(_, codes) = phase {
+            verifyCode = ""
+            phase = .backupCodes(codes)
+            status = .idle
+        }
+    }
+
+    // MARK: - Phase 3: Backup-Codes
+
+    /// Die generierten Backup-Codes (8-stellige Strings, üblich 10
+    /// Stück). UI zeigt sie zum Kopieren/Sichern.
+    public var backupCodes: [String] {
+        if case let .backupCodes(codes) = phase { return codes }
+        if case let .verify(_, codes) = phase { return codes }
+        return []
+    }
+}
diff --git a/Tests/ManaAuthUITests/TwoFactorEnrollmentViewModelTests.swift b/Tests/ManaAuthUITests/TwoFactorEnrollmentViewModelTests.swift
new file mode 100644
index 0000000..1c22ac6
--- /dev/null
+++ b/Tests/ManaAuthUITests/TwoFactorEnrollmentViewModelTests.swift
@@ -0,0 +1,130 @@
+import Foundation
+import ManaCore
+import Testing
+@testable import ManaAuthUI
+
+@Suite("TwoFactorEnrollmentViewModel")
+@MainActor
+struct TwoFactorEnrollmentViewModelTests {
+    private func signedInAuth() async -> MockedAuth {
+        let mocked = makeMockedAuth()
+        let access = "eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJ1MSIsImV4cCI6MjAwMDAwMDAwMH0.sig"
+        mocked.setHandler { _ in
+            (200, Data(#"{"accessToken":"\#(access)","refreshToken":"session-tok"}"#.utf8))
+        }
+        await mocked.auth.signIn(email: "u@x.de", password: "pw")
+        return mocked
+    }
+
+    @Test("enrollWithPassword erfolgreich → phase wechselt auf verify")
+    func enrollSuccess() async {
+        let mocked = await signedInAuth()
+        let model = TwoFactorEnrollmentViewModel(auth: mocked.auth)
+        model.password = "pw"
+
+        mocked.setHandler { _ in
+            (200, Data(#"""
+            {"totpURI":"otpauth://totp/Mana:u@x.de?secret=ABC","backupCodes":["a","b","c"]}
+            """#.utf8))
+        }
+
+        await model.enrollWithPassword()
+        if case let .verify(uri, codes) = model.phase {
+            #expect(uri.hasPrefix("otpauth://totp/"))
+            #expect(codes == ["a", "b", "c"])
+        } else {
+            Issue.record("Expected .verify, got \(model.phase)")
+        }
+        #expect(model.password == "") // out of memory
+    }
+
+    @Test("enrollWithPassword falsches PW → .error, phase bleibt password")
+    func enrollWrongPassword() async {
+        let mocked = await signedInAuth()
+        let model = TwoFactorEnrollmentViewModel(auth: mocked.auth)
+        model.password = "wrong"
+
+        mocked.setHandler { _ in
+            (401, Data(#"{"error":"INVALID_CREDENTIALS","status":401}"#.utf8))
+        }
+
+        await model.enrollWithPassword()
+        if case .password = model.phase {
+            #expect(Bool(true))
+        } else {
+            Issue.record("Expected .password, got \(model.phase)")
+        }
+        if case let .error(message) = model.status {
+            #expect(message == "Email oder Passwort falsch")
+        } else {
+            Issue.record("Expected .error, got \(model.status)")
+        }
+    }
+
+    @Test("canSubmitVerify fordert 6 Ziffern")
+    func canSubmitVerify() async {
+        let mocked = await signedInAuth()
+        let model = TwoFactorEnrollmentViewModel(auth: mocked.auth)
+        model.password = "pw"
+        mocked.setHandler { _ in
+            (200, Data(#"""
+            {"totpURI":"otpauth://totp/X","backupCodes":["a"]}
+            """#.utf8))
+        }
+        await model.enrollWithPassword()
+
+        model.verifyCode = ""
+        #expect(model.canSubmitVerify == false)
+        model.verifyCode = "12345"
+        #expect(model.canSubmitVerify == false)
+        model.verifyCode = "123456"
+        #expect(model.canSubmitVerify == true)
+        model.verifyCode = "abcdef"
+        #expect(model.canSubmitVerify == false)
+    }
+
+    @Test("confirmVerify wechselt von verify auf backupCodes")
+    func confirmVerifySwitchesPhase() async {
+        let mocked = await signedInAuth()
+        let model = TwoFactorEnrollmentViewModel(auth: mocked.auth)
+        model.password = "pw"
+        mocked.setHandler { _ in
+            (200, Data(#"""
+            {"totpURI":"otpauth://totp/X","backupCodes":["a","b","c"]}
+            """#.utf8))
+        }
+        await model.enrollWithPassword()
+        model.verifyCode = "123456"
+
+        model.confirmVerify()
+        if case let .backupCodes(codes) = model.phase {
+            #expect(codes == ["a", "b", "c"])
+        } else {
+            Issue.record("Expected .backupCodes, got \(model.phase)")
+        }
+        #expect(model.verifyCode == "")
+    }
+
+    @Test("backupCodes computed property returnt Codes aus verify- und backupCodes-Phase")
+    func backupCodesAccessor() async {
+        let mocked = await signedInAuth()
+        let model = TwoFactorEnrollmentViewModel(auth: mocked.auth)
+        // Phase .password → keine Codes
+        #expect(model.backupCodes == [])
+
+        model.password = "pw"
+        mocked.setHandler { _ in
+            (200, Data(#"""
+            {"totpURI":"otpauth://totp/X","backupCodes":["c1","c2"]}
+            """#.utf8))
+        }
+        await model.enrollWithPassword()
+        // Phase .verify → Codes verfügbar
+        #expect(model.backupCodes == ["c1", "c2"])
+
+        model.verifyCode = "123456"
+        model.confirmVerify()
+        // Phase .backupCodes → Codes weiter verfügbar
+        #expect(model.backupCodes == ["c1", "c2"])
+    }
+}