diff --git a/app/forms.py b/app/forms.py
index e674a9c..86b0b81 100644
--- a/app/forms.py
+++ b/app/forms.py
@@ -20,4 +20,5 @@ class SnippetForm(FlaskForm):
     language = SelectField("Language", choices=LANGUAGES)
     code = TextAreaField("Code", validators=[DataRequired()])
     description = StringField("Description", validators=[Length(max=200)])
+    collection = StringField("Collection", validators=[Length(max=50)])
     tags = StringField("Tags (comma separated)")
\ No newline at end of file
diff --git a/app/models.py b/app/models.py
index 8e6efba..727a403 100644
--- a/app/models.py
+++ b/app/models.py
@@ -1,6 +1,6 @@
 from datetime import datetime, UTC
 
-def make_snippet(title, language, code, description, tags):
+def make_snippet(title, language, code, description, tags, collection=""):
     """
     Returns a clean snippet document ready to insert into MongoDB.
     Centralizing this means if we ever change the schema,
@@ -12,6 +12,7 @@ def make_snippet(title, language, code, description, tags):
         "code": code,
         "description": description,
         "tags": tags,
+        "collection": collection,
         "created_at": datetime.now(UTC),
         "updated_at": datetime.now(UTC)
         
diff --git a/app/routes.py b/app/routes.py
index 9ffbaa8..d1be722 100644
--- a/app/routes.py
+++ b/app/routes.py
@@ -18,6 +18,7 @@ def index():
     query = request.args.get("q", "")
     tag = request.args.get("tag", "")
     language = request.args.get("language", "")
+    collection = request.args.get("collection", "")
     page = request.args.get("page", 1, type=int)
     page = max(page, 1)
 
@@ -32,6 +33,8 @@ def index():
         filters["tags"] = tag
     if language:
         filters["language"] = language
+    if collection:
+        filters["collection"] = collection
 
     total_snippets = snippets_collection.count_documents(filters)
     total_pages = ceil(total_snippets / PAGE_SIZE) if total_snippets else 0
@@ -47,12 +50,14 @@ def index():
     )
 
     languages = snippets_collection.distinct("language")
+    collections = snippets_collection.distinct("collection")
     pagination_params = {
         key: value
         for key, value in {
             "q": query,
             "tag": tag,
             "language": language,
+            "collection": collection,
         }.items()
         if value
     }
@@ -64,7 +69,9 @@ def index():
         query=query,
         tag=tag,
         language=language,
+        collection=collection,
         languages=languages,
+        collections=[c for c in collections if c],
         page=page,
         total_pages=total_pages,
         pagination_params=pagination_params,
@@ -82,6 +89,7 @@ def add_snippet():
             code=form.code.data,
             description=form.description.data,
             tags=tags,
+            collection=form.collection.data,
         )
         snippets_collection.insert_one(snippet)
         flash("Snip saved successfully!", "success")
@@ -120,6 +128,7 @@ def edit_snippet(id):
                     "language": form.language.data,
                     "code": form.code.data,
                     "description": form.description.data,
+                    "collection": form.collection.data,
                     "tags": tags,
                     "updated_at": datetime.now(UTC),
                 }
@@ -133,6 +142,7 @@ def edit_snippet(id):
     form.language.data = snippet["language"]
     form.code.data = snippet["code"]
     form.description.data = snippet.get("description", "")
+    form.collection.data = snippet.get("collection", "")
     form.tags.data = ", ".join(snippet.get("tags", []))
 
     return render_template("edit.html", form=form, snippet=snippet)
diff --git a/app/templates/add.html b/app/templates/add.html
index 12a0383..552432b 100644
--- a/app/templates/add.html
+++ b/app/templates/add.html
@@ -21,6 +21,11 @@ <h1>New Snip</h1>
             {{ form.description(placeholder="What does this snippet do?") }}
         </div>
 
+        <div class="form-group">
+            {{ form.collection.label }}
+            {{ form.collection(placeholder="e.g. Work, Side Project, Personal") }}
+        </div>
+
         <div class="form-group">
             {{ form.code.label }}
             {{ form.code(placeholder="Paste your code here...", rows=12) }}
diff --git a/app/templates/edit.html b/app/templates/edit.html
index 0c224a7..d0837ab 100644
--- a/app/templates/edit.html
+++ b/app/templates/edit.html
@@ -21,6 +21,11 @@ <h1>Edit Snip</h1>
             {{ form.description() }}
         </div>
 
+        <div class="form-group">
+            {{ form.collection.label }}
+            {{ form.collection() }}
+        </div>
+
         <div class="form-group">
             {{ form.code.label }}
             {{ form.code(rows=12) }}
diff --git a/app/templates/index.html b/app/templates/index.html
index 92146b6..9a77aba 100644
--- a/app/templates/index.html
+++ b/app/templates/index.html
@@ -15,8 +15,14 @@ <h1>My Snips</h1>
             <option value="{{ lang }}" {% if lang == language %}selected{% endif %}>{{ lang }}</option>
             {% endfor %}
         </select>
+        <select name="collection">
+            <option value="">All Collections</option>
+            {% for coll in collections %}
+            <option value="{{ coll }}" {% if coll == collection %}selected{% endif %}>{{ coll }}</option>
+            {% endfor %}
+        </select>
         <button type="submit">Search</button>
-        {% if query or tag or language %}
+        {% if query or tag or language or collection %}
         <a href="/" class="clear-btn">Clear</a>
         {% endif %}
     </form>
@@ -49,6 +55,9 @@ <h1>My Snips</h1>
         </div>
         <div class="card-header">
             <span class="language-badge">{{ snippet.language }}</span>
+            {% if snippet.collection %}
+            <span class="language-badge" style="background-color: var(--bg-alt); color: var(--text-muted); border: 1px solid var(--border);">{{ snippet.collection }}</span>
+            {% endif %}
             <a href="/snippet/{{ snippet._id }}" class="card-title">{{ snippet.title }}</a>
         </div>
         {% if snippet.description %}
diff --git a/app/templates/snippet.html b/app/templates/snippet.html
index 714eccb..7b0efff 100644
--- a/app/templates/snippet.html
+++ b/app/templates/snippet.html
@@ -5,6 +5,9 @@
     <div class="detail-header">
         <div>
             <span class="language-badge">{{ snippet.language }}</span>
+            {% if snippet.collection %}
+            <span class="language-badge" style="background-color: var(--bg-alt); color: var(--text-muted); border: 1px solid var(--border);">{{ snippet.collection }}</span>
+            {% endif %}
             <h1>{{ snippet.title }}</h1>
             {% if snippet.description %}
                 <p class="description">{{ snippet.description }}</p>
diff --git a/tests/test_routes.py b/tests/test_routes.py
index e89d915..7f4d84b 100644
--- a/tests/test_routes.py
+++ b/tests/test_routes.py
@@ -188,3 +188,19 @@ def test_pagination_handles_empty_results(client, fake_collection):
     assert response.status_code == 200
     assert b"0 snippets found" in response.data
     assert b"Page 1 of" not in response.data
+
+
+def test_filter_by_collection(client, fake_collection):
+    """Home page should filter snippets by collection"""
+    snip1 = make_test_snippet(1)
+    snip1["collection"] = "Work"
+    snip2 = make_test_snippet(2)
+    snip2["collection"] = "Personal"
+    fake_collection.documents = [snip1, snip2]
+
+    response = client.get("/?collection=Work")
+    assert response.status_code == 200
+    assert b"1 snippet found" in response.data
+    assert b"Snippet 01" in response.data
+    assert b"Snippet 02" not in response.data
+