diff --git a/lib/atomic/activities/session.ex b/lib/atomic/activities/session.ex
index 39a957822..f62875764 100644
--- a/lib/atomic/activities/session.ex
+++ b/lib/atomic/activities/session.ex
@@ -48,6 +48,7 @@ defmodule Atomic.Activities.Session do
     |> cast(attrs, @required_fields ++ @optional_fields)
     |> validate_required(@required_fields)
     |> validate_location()
+    |> check_constraint(:minimum_entries, name: :minimum_entries_lower_than_maximum_entries)
     |> maybe_mark_for_deletion()
     |> maybe_put_departments(attrs)
     |> maybe_put_speakers(attrs)
diff --git a/priv/repo/migrations/20221023200102_create_sessions.exs b/priv/repo/migrations/20221023200102_create_sessions.exs
index d189ddf8d..877b59bdd 100644
--- a/priv/repo/migrations/20221023200102_create_sessions.exs
+++ b/priv/repo/migrations/20221023200102_create_sessions.exs
@@ -18,5 +18,9 @@ defmodule Atomic.Repo.Migrations.CreateSessions do
     end
 
     create index(:sessions, [:activity_id])
+
+    create constraint(:sessions, :minimum_entries_lower_than_maximum_entries,
+             check: "minimum_entries < maximum_entries"
+           )
   end
 end
diff --git a/test/support/fixtures/activities_fixtures.ex b/test/support/fixtures/activities_fixtures.ex
index 946462121..350eb5c3a 100644
--- a/test/support/fixtures/activities_fixtures.ex
+++ b/test/support/fixtures/activities_fixtures.ex
@@ -29,7 +29,7 @@ defmodule Atomic.ActivitiesFixtures do
       attrs
       |> Enum.into(%{
         maximum_entries: 42,
-        minimum_entries: 42,
+        minimum_entries: 0,
         finish: ~N[2022-10-22 20:00:00],
         start: ~N[2022-10-22 20:00:00]
       })