diff --git a/internal/cli/cli.go b/internal/cli/cli.go
index e7ab2d4..15d6b75 100644
--- a/internal/cli/cli.go
+++ b/internal/cli/cli.go
@@ -31,6 +31,7 @@ Usage:
                     [--desc FILE|-] [--note TEXT] [-o json]
   mred version list -p PROJECT [-o json]
   mred version create -p PROJECT -n NAME [--due DATE] [--status open|closed] [-o json]
+  mred version update ID [--status open|closed] [--due DATE] [--name NAME] [-o json]
   mred category list -p PROJECT [-o json]
   mred category create -p PROJECT -n NAME [-o json]
   mred relation create FROM TO --type blocks|relates [-o json]
diff --git a/internal/cli/cli_test.go b/internal/cli/cli_test.go
index 50a2909..9960a87 100644
--- a/internal/cli/cli_test.go
+++ b/internal/cli/cli_test.go
@@ -255,6 +255,124 @@ func TestVersionCommands(t *testing.T) {
 	}
 }
 
+func TestVersionUpdate(t *testing.T) {
+	tests := []struct {
+		name    string
+		args    []string // ID placeholder "@" replaced with the seeded id
+		wantOut string   // substring expected on stdout
+		wantVer fakeredmine.Version
+		wantCode int
+	}{
+		{
+			name:    "status flip",
+			args:    []string{"@", "--status", "closed"},
+			wantOut: "updated version #",
+			wantVer: fakeredmine.Version{Name: "Beta", DueDate: "2026-08-31", Status: "closed"},
+		},
+		{
+			name:    "due change",
+			args:    []string{"@", "--due", "2026-09-15"},
+			wantVer: fakeredmine.Version{Name: "Beta", DueDate: "2026-09-15", Status: "open"},
+		},
+		{
+			name:    "name change",
+			args:    []string{"@", "--name", "Beta 2"},
+			wantVer: fakeredmine.Version{Name: "Beta 2", DueDate: "2026-08-31", Status: "open"},
+		},
+		{
+			name:    "combined flags",
+			args:    []string{"@", "--status", "closed", "--due", "2026-09-15", "--name", "Gamma"},
+			wantVer: fakeredmine.Version{Name: "Gamma", DueDate: "2026-09-15", Status: "closed"},
+		},
+		{
+			name:     "no flags is a usage error",
+			args:     []string{"@"},
+			wantCode: 1,
+		},
+		{
+			name:     "bad status is a usage error",
+			args:     []string{"@", "--status", "deferred"},
+			wantCode: 1,
+		},
+		{
+			name:     "non-numeric id is a usage error",
+			args:     []string{"beta", "--status", "closed"},
+			wantCode: 1,
+		},
+		{
+			name:     "unknown version id is exit 2",
+			args:     []string{"424242", "--status", "closed"},
+			wantCode: 2,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			srv := boot(t)
+			id := srv.AddVersion(fakeredmine.Version{Name: "Beta", DueDate: "2026-08-31", Status: "open"})
+			args := make([]string, len(tt.args))
+			for i, a := range tt.args {
+				if a == "@" {
+					args[i] = itoa(id)
+				} else {
+					args[i] = a
+				}
+			}
+			out, errb, code := run(t, append([]string{"version", "update"}, args...)...)
+			wantCode := tt.wantCode
+			if wantCode == 0 {
+				if !strings.Contains(out, tt.wantOut) || !strings.Contains(out, itoa(id)) {
+					t.Errorf("out = %q, want %q + id %d", out, tt.wantOut, id)
+				}
+				got, ok := srv.Version(id)
+				if !ok {
+					t.Fatalf("version %d vanished", id)
+				}
+				if got.Name != tt.wantVer.Name || got.DueDate != tt.wantVer.DueDate || got.Status != tt.wantVer.Status {
+					t.Errorf("stored = %+v, want %+v", got, tt.wantVer)
+				}
+			} else {
+				if out != "" {
+					t.Errorf("usage error wrote to stdout: %q", out)
+				}
+				if errb == "" {
+					t.Errorf("no diagnostic on stderr")
+				}
+				if tt.wantCode == 2 && !strings.Contains(errb, "http 404") {
+					t.Errorf("stderr = %q, want http 404", errb)
+				}
+			}
+			if code != wantCode {
+				t.Fatalf("code = %d, want %d (stderr %q)", code, wantCode, errb)
+			}
+		})
+	}
+}
+
+func TestVersionUpdateJSONRefetches(t *testing.T) {
+	srv := boot(t)
+	id := srv.AddVersion(fakeredmine.Version{Name: "Beta", DueDate: "2026-08-31", Status: "open"})
+
+	out, errb, code := run(t, "version", "update", itoa(id), "--status", "closed", "-o", "json")
+	if code != 0 {
+		t.Fatalf("code = %d, stderr = %q", code, errb)
+	}
+	var got struct {
+		Version struct {
+			ID      int    `json:"id"`
+			Name    string `json:"name"`
+			DueDate string `json:"due_date"`
+			Status  string `json:"status"`
+		} `json:"version"`
+	}
+	if err := json.Unmarshal([]byte(out), &got); err != nil {
+		t.Fatalf("stdout not json: %v (%q)", err, out)
+	}
+	v := got.Version
+	if v.ID != id || v.Name != "Beta" || v.DueDate != "2026-08-31" || v.Status != "closed" {
+		t.Errorf("refetched version = %+v", v)
+	}
+}
+
 func TestCategoryCommands(t *testing.T) {
 	boot(t)
 	_, errb, code := run(t, "category", "create", "-p", "MOPAC", "-n", "Secrets")
diff --git a/internal/cli/commands.go b/internal/cli/commands.go
index afa1e41..d8f029c 100644
--- a/internal/cli/commands.go
+++ b/internal/cli/commands.go
@@ -356,7 +356,7 @@ func readDesc(path string) (string, error) {
 
 func cmdVersion(args []string, stdout, stderr io.Writer) int {
 	if len(args) == 0 {
-		return usageErr(stderr, "version: expected list|create (see mred help)")
+		return usageErr(stderr, "version: expected list|create|update (see mred help)")
 	}
 	sub, rest := args[0], args[1:]
 	switch sub {
@@ -364,6 +364,8 @@ func cmdVersion(args []string, stdout, stderr io.Writer) int {
 		return cmdVersionList(rest, stdout, stderr)
 	case "create":
 		return cmdVersionCreate(rest, stdout, stderr)
+	case "update":
+		return cmdVersionUpdate(rest, stdout, stderr)
 	default:
 		return usageErr(stderr, "version: unknown subcommand %q", sub)
 	}
@@ -432,6 +434,48 @@ func dueSuffix(due string) string {
 	return "due " + due
 }
 
+func cmdVersionUpdate(args []string, stdout, stderr io.Writer) int {
+	fs, cfgPath, out := newFlags("version update", stderr)
+	status := fs.String("status", "", "open|closed")
+	due := fs.String("due", "", "due date YYYY-MM-DD")
+	name := fs.String("name", "", "new version name")
+	pos, perr := parseArgs(fs, args)
+	if perr != nil || len(pos) != 1 {
+		return usageErr(stderr, "version update: usage: mred version update ID [--status open|closed] [--due DATE] [--name NAME]")
+	}
+	id, err := strconv.Atoi(pos[0])
+	if err != nil {
+		return usageErr(stderr, "version update: ID must be numeric, got %q", pos[0])
+	}
+	if *status == "" && *due == "" && *name == "" {
+		return usageErr(stderr, "version update: nothing to update: pass at least one of --status, --due, --name")
+	}
+	if *status != "" && *status != "open" && *status != "closed" {
+		return usageErr(stderr, "version update: --status must be open|closed")
+	}
+	c, err := client(*cfgPath)
+	if err != nil {
+		return usageErr(stderr, "%v", err)
+	}
+	// The server answers 204 with an empty body; UpdateVersion never
+	// parses it. -o json re-fetches the version afterwards.
+	if err := c.UpdateVersion(context.Background(), id, redmine.VersionParams{
+		Name: *name, DueDate: *due, Status: *status,
+	}); err != nil {
+		return apiErr(stderr, err)
+	}
+	if *out == "json" {
+		v, err := c.GetVersion(context.Background(), id)
+		if err != nil {
+			return apiErr(stderr, err)
+		}
+		emitJSON(stdout, map[string]any{"version": v})
+		return 0
+	}
+	fmt.Fprintf(stdout, "updated version #%d\n", id)
+	return 0
+}
+
 // --- category -----------------------------------------------------------------
 
 func cmdCategory(args []string, stdout, stderr io.Writer) int {