diff --git a/README.md b/README.md
index 91ae23c..8beaffa 100644
--- a/README.md
+++ b/README.md
@@ -25,7 +25,7 @@ WinterCMS theme components such as `journalPost` and `journalPosts` are a later
 - **Author slug.** Plugin migration adds `backend_users.golem15_bloghub_author_slug`. The column stores the public author slug that the author routes resolve.
 - **Import and export.** `journal:export-posts` and `journal:import-posts` write and read one JSON file per post. The Posts list toolbar exposes the same actions to administrators with `golem15.journal.access_import_export`.
 - **Phrasebooks.** Embedded `lang/en/lang.yaml` and `lang/pl/lang.yaml` hold plugin, journal, post, category, and tag UI strings. They are independent of model translation JSON.
-- **Schema.** Seven gormigrate steps create the six journal tables and the author-slug column. AutoMigrate is not used. Table names are `golem15_journal_*` only.
+- **Schema.** Eight gormigrate steps create the six journal tables, the author-slug column and the category `content` column. AutoMigrate is not used. Table names are `golem15_journal_*` only.
 
 ## Usage
 
@@ -80,6 +80,16 @@ GET /_journal/api/v1/authors/jane-doe
 GET /_journal/api/v1/authors/jane-doe/posts?page=2
 ```
 
+### Public categories API
+
+`GET /_journal/api/v1/categories` returns `{"data":[...]}`, a tree of category rows. Each row has the keys `id`, `name`, `slug`, `description`, `content`, `parent_id`, `nest_depth` and `post_count`, plus `children` only when the category has listed children. A category with no published posts and no listed children is omitted unless the request adds `include_empty=1`.
+
+`content` is the category's HTML body for a category landing page. It is stored and returned as is: it is not markdown and the API does not render, trim or sanitize it. It is `null` when unset, and it is the same in every locale, because it is a host column and not translatable. A consumer that renders it as HTML must apply its own gate or sanitizer first.
+
+```json
+{"data":[{"id":4,"name":"Acme news","slug":"news","description":null,"content":"<h2>Acme news</h2><p>Pillar copy</p>","parent_id":null,"nest_depth":0,"post_count":3}]}
+```
+
 ### Public author API
 
 `GET /_journal/api/v1/authors/{author}` returns one author's public profile without a token. `{author}` resolves in this order:
@@ -157,7 +167,7 @@ func (Post) MorphName() string             { return `Golem15\Journal\Models\Post
 | `models.Post.ShouldBeSearchable` | False when unpublished or `search_use_typesense` is off. |
 | `models.Post.ToSearchableArray` | Typesense document built after a committed save. |
 | `models.Post.CanEdit` | Owner or `golem15.journal.access_other_posts`. |
-| `models.Category` | Category row; `TableName` is `golem15_journal_categories`. |
+| `models.Category` | Category row; `TableName` is `golem15_journal_categories`; `Content` holds the HTML body served as `content`. |
 | `models.Category.MorphName` | PHP class string `Golem15\Journal\Models\Category`. |
 | `models.Category.Fillable` | `name`, `slug`, `code`, `description`, `parent_id`. |
 | `models.Tag` | Tag row; `TableName` is `golem15_journal_tags`. |
diff --git a/controllers/api/categories_test.go b/controllers/api/categories_test.go
new file mode 100644
index 0000000..45143f3
--- /dev/null
+++ b/controllers/api/categories_test.go
@@ -0,0 +1,62 @@
+package api
+
+import (
+	"reflect"
+	"sort"
+	"testing"
+
+	"git.golem15.com/golem15/sm-journal-plugin/models"
+)
+
+func sortedCategoryKeys(row map[string]any) []string {
+	keys := make([]string, 0, len(row))
+	for k := range row {
+		keys = append(keys, k)
+	}
+	sort.Strings(keys)
+	return keys
+}
+
+func TestSerializeCategoryNodeContent(t *testing.T) {
+	html := "<h2>Acme</h2>\n<p>Pillar copy</p>\n"
+	var parentID uint = 1
+	root := models.Category{ID: 1, Name: "News", Slug: "news", Content: &html}
+	child := models.Category{ID: 2, Name: "Quiet", Slug: "quiet", ParentID: &parentID}
+	byParent := map[uint][]models.Category{1: {child}}
+	counts := map[uint]int64{1: 2}
+
+	row := serializeCategoryNode(&root, byParent, counts, true)
+	if row == nil {
+		t.Fatal("root row is nil")
+	}
+	if got, ok := row["content"].(string); !ok || got != html {
+		t.Fatalf("root content = %#v, want %q", row["content"], html)
+	}
+	wantRoot := []string{"children", "content", "description", "id", "name", "nest_depth", "parent_id", "post_count", "slug"}
+	if got := sortedCategoryKeys(row); !reflect.DeepEqual(got, wantRoot) {
+		t.Fatalf("root keys = %v, want %v", got, wantRoot)
+	}
+	kids, ok := row["children"].([]map[string]any)
+	if !ok || len(kids) != 1 {
+		t.Fatalf("children = %#v, want one row", row["children"])
+	}
+	v, present := kids[0]["content"]
+	if !present || v != nil {
+		t.Fatalf("child content = %#v (present %v), want nil", v, present)
+	}
+	wantChild := []string{"content", "description", "id", "name", "nest_depth", "parent_id", "post_count", "slug"}
+	if got := sortedCategoryKeys(kids[0]); !reflect.DeepEqual(got, wantChild) {
+		t.Fatalf("child keys = %v, want %v", got, wantChild)
+	}
+
+	listed := serializeCategoryNode(&root, byParent, counts, false)
+	if listed == nil {
+		t.Fatal("root omitted without include_empty")
+	}
+	if _, has := listed["children"]; has {
+		t.Fatalf("empty child listed without include_empty: %#v", listed["children"])
+	}
+	if got, ok := listed["content"].(string); !ok || got != html {
+		t.Fatalf("root content without include_empty = %#v, want %q", listed["content"], html)
+	}
+}
diff --git a/controllers/api/posts_helpers.go b/controllers/api/posts_helpers.go
index 970bc6e..86faa25 100644
--- a/controllers/api/posts_helpers.go
+++ b/controllers/api/posts_helpers.go
@@ -195,6 +195,10 @@ func serializeCategoryNode(c *models.Category, byParent map[uint][]models.Catego
 	if c.Description != nil {
 		desc = *c.Description
 	}
+	var content any
+	if c.Content != nil {
+		content = *c.Content
+	}
 	var parent any
 	if c.ParentID != nil {
 		parent = *c.ParentID
@@ -208,6 +212,7 @@ func serializeCategoryNode(c *models.Category, byParent map[uint][]models.Catego
 		"name":        c.Name,
 		"slug":        c.Slug,
 		"description": desc,
+		"content":     content,
 		"parent_id":   parent,
 		"nest_depth":  depth,
 		"post_count":  postCount,
diff --git a/journal_api_categories_test.go b/journal_api_categories_test.go
new file mode 100644
index 0000000..b096198
--- /dev/null
+++ b/journal_api_categories_test.go
@@ -0,0 +1,131 @@
+package journal_test
+
+import (
+	"encoding/json"
+	"net/http"
+	"reflect"
+	"sort"
+	"testing"
+	"time"
+
+	"git.golem15.com/golem15/sm-journal-plugin/models"
+)
+
+// flattenCategoryRows walks the categories tree (data plus children) into one
+// slice of rows.
+func flattenCategoryRows(rows []map[string]any) []map[string]any {
+	var out []map[string]any
+	for _, row := range rows {
+		out = append(out, row)
+		if kids, ok := row["children"].([]any); ok {
+			nested := make([]map[string]any, 0, len(kids))
+			for _, k := range kids {
+				if m, ok := k.(map[string]any); ok {
+					nested = append(nested, m)
+				}
+			}
+			out = append(out, flattenCategoryRows(nested)...)
+		}
+	}
+	return out
+}
+
+func categoryRowsBySlug(t *testing.T, env *adminEnv, path string) map[string]map[string]any {
+	t.Helper()
+	rec := env.expect(t, http.StatusOK, http.MethodGet, path, "", nil)
+	var body struct {
+		Data []map[string]any `json:"data"`
+	}
+	if err := json.Unmarshal(rec.Body.Bytes(), &body); err != nil {
+		t.Fatalf("categories json: %s err=%v", rec.Body.String(), err)
+	}
+	out := map[string]map[string]any{}
+	for _, row := range flattenCategoryRows(body.Data) {
+		slug, _ := row["slug"].(string)
+		out[slug] = row
+	}
+	return out
+}
+
+func assertNullContent(t *testing.T, rows map[string]map[string]any, slug string) {
+	t.Helper()
+	row, ok := rows[slug]
+	if !ok {
+		t.Fatalf("category %s not listed", slug)
+	}
+	v, present := row["content"]
+	if !present || v != nil {
+		t.Fatalf("%s content = %#v (present %v), want JSON null", slug, v, present)
+	}
+}
+
+func TestJournalCategoryContentAPI(t *testing.T) {
+	env := newPostsEnv(t)
+	html := "<h2>Acme news</h2>\n<p>Pillar copy</p>"
+	left, right, depth := 3, 4, 0
+	news := models.Category{Name: "News", Slug: "news", Content: &html, NestLeft: &left, NestRight: &right, NestDepth: &depth}
+	if err := env.gdb.Create(&news).Error; err != nil {
+		t.Fatal(err)
+	}
+	quiet := models.Category{Name: "Quiet", Slug: "quiet"}
+	if err := env.gdb.Create(&quiet).Error; err != nil {
+		t.Fatal(err)
+	}
+	past := time.Now().UTC().Add(-time.Hour)
+	post := models.Post{Title: "Listed", Slug: "listed-content", Content: "x", Published: true, PublishedAt: &past}
+	if err := env.gdb.Create(&post).Error; err != nil {
+		t.Fatal(err)
+	}
+	if err := env.gdb.Create(&models.PostCategory{PostID: post.ID, CategoryID: news.ID}).Error; err != nil {
+		t.Fatal(err)
+	}
+
+	all := categoryRowsBySlug(t, env, "/_journal/api/v1/categories?include_empty=1")
+	if got, ok := all["news"]["content"].(string); !ok || got != html {
+		t.Fatalf("news content = %#v, want %q", all["news"]["content"], html)
+	}
+	assertNullContent(t, all, "quiet")
+	assertNullContent(t, all, "uncategorized")
+
+	listed := categoryRowsBySlug(t, env, "/_journal/api/v1/categories")
+	if got, ok := listed["news"]["content"].(string); !ok || got != html {
+		t.Fatalf("news content without include_empty = %#v, want %q", listed["news"]["content"], html)
+	}
+	if _, ok := listed["quiet"]; ok {
+		t.Fatal("empty category quiet listed without include_empty")
+	}
+
+	rec := env.expect(t, http.StatusOK, http.MethodGet, "/_journal/api/v1/posts", "", nil)
+	var posts struct {
+		Data []map[string]any `json:"data"`
+	}
+	if err := json.Unmarshal(rec.Body.Bytes(), &posts); err != nil {
+		t.Fatalf("posts json: %s err=%v", rec.Body.String(), err)
+	}
+	var found bool
+	for _, p := range posts.Data {
+		if p["slug"] != "listed-content" {
+			continue
+		}
+		found = true
+		cats, ok := p["categories"].([]any)
+		if !ok || len(cats) == 0 {
+			t.Fatalf("post categories = %#v", p["categories"])
+		}
+		first, ok := cats[0].(map[string]any)
+		if !ok {
+			t.Fatalf("post category entry = %#v", cats[0])
+		}
+		keys := make([]string, 0, len(first))
+		for k := range first {
+			keys = append(keys, k)
+		}
+		sort.Strings(keys)
+		if want := []string{"id", "name", "slug"}; !reflect.DeepEqual(keys, want) {
+			t.Fatalf("post category keys = %v, want %v", keys, want)
+		}
+	}
+	if !found {
+		t.Fatalf("post listed-content missing from /posts: %s", rec.Body.String())
+	}
+}
diff --git a/models/category.go b/models/category.go
index d8e7f19..0dc3659 100644
--- a/models/category.go
+++ b/models/category.go
@@ -9,6 +9,7 @@ type Category struct {
 	Slug        string     `gorm:"column:slug"`
 	Code        *string    `gorm:"column:code"`
 	Description *string    `gorm:"column:description"`
+	Content     *string    `gorm:"column:content"` // HTML body (D-21): stored and served as is, not translatable
 	ParentID    *uint      `gorm:"column:parent_id"`
 	NestLeft    *int       `gorm:"column:nest_left"`
 	NestRight   *int       `gorm:"column:nest_right"`
diff --git a/updates/202610090001_add_content_to_golem15_journal_categories.go b/updates/202610090001_add_content_to_golem15_journal_categories.go
new file mode 100644
index 0000000..6f0a5f3
--- /dev/null
+++ b/updates/202610090001_add_content_to_golem15_journal_categories.go
@@ -0,0 +1,24 @@
+package updates
+
+import (
+	"github.com/go-gormigrate/gormigrate/v2"
+	"gorm.io/gorm"
+)
+
+// addCategoryContent adds the category HTML body (D-21). It must stay the last
+// migration so RollbackLast drops only this column and keeps the rows.
+var addCategoryContent = []*gormigrate.Migration{
+	{
+		ID: "202610090001_add_content_to_golem15_journal_categories",
+		Migrate: func(tx *gorm.DB) error {
+			return tx.Exec(`ALTER TABLE golem15_journal_categories ADD COLUMN IF NOT EXISTS content TEXT NULL`).Error
+		},
+		Rollback: func(tx *gorm.DB) error {
+			return tx.Exec(`ALTER TABLE golem15_journal_categories DROP COLUMN IF EXISTS content`).Error
+		},
+	},
+}
+
+func init() {
+	Register(addCategoryContent...)
+}
diff --git a/updates/category_content_migration_test.go b/updates/category_content_migration_test.go
new file mode 100644
index 0000000..4cf1873
--- /dev/null
+++ b/updates/category_content_migration_test.go
@@ -0,0 +1,82 @@
+package updates
+
+import (
+	"database/sql"
+	"fmt"
+	"testing"
+	"time"
+
+	"git.golem15.com/golem15/summercms/modules/lagoon"
+	"github.com/go-gormigrate/gormigrate/v2"
+)
+
+func TestCategoryContentMigration(t *testing.T) {
+	sqlDB := dedicatedDB(t, fmt.Sprintf("journal_catcontent_%d", time.Now().UnixNano()))
+	gdb, err := lagoon.Use(t.Context(), sqlDB)
+	if err != nil {
+		t.Fatal(err)
+	}
+	backend := gormigrate.New(gdb, &gormigrate.Options{
+		TableName:      "summer_migrations_summercms_cabana",
+		UseTransaction: true,
+	}, lagoon.BackendAdminMigrations)
+	if err := backend.Migrate(); err != nil {
+		t.Fatalf("backend_users migrations: %v", err)
+	}
+	m := journalMigrator(gdb)
+	if err := m.Migrate(); err != nil {
+		t.Fatalf("migrate: %v", err)
+	}
+
+	all := All()
+	if last := all[len(all)-1].ID; last != "202610090001_add_content_to_golem15_journal_categories" {
+		t.Fatalf("last migration = %s, want 202610090001_add_content_to_golem15_journal_categories", last)
+	}
+	if !gdb.Migrator().HasColumn("golem15_journal_categories", "content") {
+		t.Fatal("golem15_journal_categories.content missing")
+	}
+	assertUdt(t, gdb, "golem15_journal_categories", "content", "text")
+	var nullable string
+	if err := gdb.WithContext(t.Context()).Raw(
+		`SELECT is_nullable FROM information_schema.columns WHERE table_name = 'golem15_journal_categories' AND column_name = 'content'`,
+	).Scan(&nullable).Error; err != nil {
+		t.Fatal(err)
+	}
+	if nullable != "YES" {
+		t.Fatalf("content is_nullable = %q, want YES", nullable)
+	}
+
+	if err := gdb.Exec(`UPDATE golem15_journal_categories SET content = '<p>x</p>' WHERE slug = 'uncategorized'`).Error; err != nil {
+		t.Fatal(err)
+	}
+	if err := m.RollbackLast(); err != nil {
+		t.Fatalf("rollback last: %v", err)
+	}
+	if !gdb.Migrator().HasTable("golem15_journal_categories") {
+		t.Fatal("golem15_journal_categories dropped by the content rollback")
+	}
+	if gdb.Migrator().HasColumn("golem15_journal_categories", "content") {
+		t.Fatal("content column survived rollback")
+	}
+	var rows int64
+	if err := gdb.Raw(`SELECT COUNT(*) FROM golem15_journal_categories WHERE slug = 'uncategorized'`).Scan(&rows).Error; err != nil {
+		t.Fatal(err)
+	}
+	if rows != 1 {
+		t.Fatalf("uncategorized rows after rollback = %d, want 1", rows)
+	}
+
+	if err := m.Migrate(); err != nil {
+		t.Fatalf("re-migrate: %v", err)
+	}
+	if !gdb.Migrator().HasColumn("golem15_journal_categories", "content") {
+		t.Fatal("content column missing after re-migrate")
+	}
+	var content sql.NullString
+	if err := gdb.Raw(`SELECT content FROM golem15_journal_categories WHERE slug = 'uncategorized'`).Scan(&content).Error; err != nil {
+		t.Fatal(err)
+	}
+	if content.Valid {
+		t.Fatalf("uncategorized content after re-migrate = %q, want NULL", content.String)
+	}
+}