diff --git a/internal/store/hosts.go b/internal/store/hosts.go
index 18d5c7d..8dad905 100644
--- a/internal/store/hosts.go
+++ b/internal/store/hosts.go
@@ -44,7 +44,7 @@ func (s *Store) LookupHostByAgentToken(ctx context.Context, tokenHash string) (*
 			repo_size_bytes, snapshot_count, open_alert_count,
 			applied_schedule_version, bandwidth_up_kbps, bandwidth_down_kbps,
 			pre_hook_default, post_hook_default,
-			repo_status, repo_status_error
+			repo_status, repo_status_error, always_on
 		 FROM hosts WHERE agent_token_hash = ?`,
 		tokenHash)
 	return scanHost(row)
@@ -59,7 +59,7 @@ func (s *Store) GetHost(ctx context.Context, id string) (*Host, error) {
 			repo_size_bytes, snapshot_count, open_alert_count,
 			applied_schedule_version, bandwidth_up_kbps, bandwidth_down_kbps,
 			pre_hook_default, post_hook_default,
-			repo_status, repo_status_error
+			repo_status, repo_status_error, always_on
 		 FROM hosts WHERE id = ?`, id)
 	return scanHost(row)
 }
@@ -227,7 +227,7 @@ func (s *Store) ListHosts(ctx context.Context) ([]Host, error) {
 			repo_size_bytes, snapshot_count, open_alert_count,
 			applied_schedule_version, bandwidth_up_kbps, bandwidth_down_kbps,
 			pre_hook_default, post_hook_default,
-			repo_status, repo_status_error
+			repo_status, repo_status_error, always_on
 		 FROM hosts ORDER BY name`)
 	if err != nil {
 		return nil, fmt.Errorf("store: list hosts: %w", err)
@@ -267,6 +267,7 @@ func scanHostRow(s hostScanner) (*Host, error) {
 		tags                         string
 		bwUp, bwDown                 sql.NullInt64
 		preHook, postHook            sql.NullString
+		alwaysOn                     int
 	)
 	err := s.Scan(&h.ID, &h.Name, &h.OS, &h.Arch,
 		&h.AgentVersion, &h.ResticVersion, &h.ProtocolVersion,
@@ -275,7 +276,7 @@ func scanHostRow(s hostScanner) (*Host, error) {
 		&h.RepoSizeBytes, &h.SnapshotCount, &h.OpenAlertCount,
 		&h.AppliedScheduleVersion, &bwUp, &bwDown,
 		&preHook, &postHook,
-		&h.RepoStatus, &h.RepoStatusError)
+		&h.RepoStatus, &h.RepoStatusError, &alwaysOn)
 	if err != nil {
 		if errors.Is(err, sql.ErrNoRows) {
 			return nil, ErrNotFound
@@ -330,6 +331,7 @@ func scanHostRow(s hostScanner) (*Host, error) {
 	if postHook.Valid {
 		h.PostHookDefault = postHook.String
 	}
+	h.AlwaysOn = alwaysOn != 0
 	return &h, nil
 }
 
@@ -378,6 +380,22 @@ func (s *Store) SetHostTags(ctx context.Context, hostID string, tags []string) e
 	return nil
 }
 
+// SetHostAlwaysOn flips the host's always-on flag. true = 24x7 server
+// (default); false = intermittent host (laptop). See the
+// always-on-host-mode spec.
+func (s *Store) SetHostAlwaysOn(ctx context.Context, hostID string, alwaysOn bool) error {
+	v := 0
+	if alwaysOn {
+		v = 1
+	}
+	_, err := s.db.ExecContext(ctx,
+		`UPDATE hosts SET always_on = ? WHERE id = ?`, v, hostID)
+	if err != nil {
+		return fmt.Errorf("store: set host always_on: %w", err)
+	}
+	return nil
+}
+
 // DistinctHostTags returns the union of every tag in use across the
 // fleet, sorted. Powers the autocomplete on the host-tags editor and
 // the chip-row filter on the dashboard. Cheap at fleet sizes this
diff --git a/internal/store/hosts_always_on_test.go b/internal/store/hosts_always_on_test.go
new file mode 100644
index 0000000..8f9cf04
--- /dev/null
+++ b/internal/store/hosts_always_on_test.go
@@ -0,0 +1,46 @@
+package store
+
+import (
+	"context"
+	"testing"
+	"time"
+)
+
+func TestHostAlwaysOnDefaultAndToggle(t *testing.T) {
+	ctx := context.Background()
+	st := openTestStore(t)
+
+	h := Host{
+		ID: "h-always-on", Name: "lap", OS: "linux", Arch: "amd64",
+		ProtocolVersion: 1, EnrolledAt: time.Now().UTC(),
+	}
+	if err := st.CreateHost(ctx, h, "tok-hash", "pin"); err != nil {
+		t.Fatalf("create host: %v", err)
+	}
+	got, err := st.GetHost(ctx, h.ID)
+	if err != nil {
+		t.Fatalf("get host: %v", err)
+	}
+	if !got.AlwaysOn {
+		t.Fatalf("new host should default to always_on=true, got false")
+	}
+
+	if err := st.SetHostAlwaysOn(ctx, h.ID, false); err != nil {
+		t.Fatalf("set always_on: %v", err)
+	}
+	got, err = st.GetHost(ctx, h.ID)
+	if err != nil {
+		t.Fatalf("get host 2: %v", err)
+	}
+	if got.AlwaysOn {
+		t.Fatalf("expected always_on=false after toggle, got true")
+	}
+
+	hosts, err := st.ListHosts(ctx)
+	if err != nil {
+		t.Fatalf("list hosts: %v", err)
+	}
+	if len(hosts) != 1 || hosts[0].AlwaysOn {
+		t.Fatalf("ListHosts should report always_on=false, got %+v", hosts)
+	}
+}
diff --git a/internal/store/migrations/0024_hosts_always_on.sql b/internal/store/migrations/0024_hosts_always_on.sql
new file mode 100644
index 0000000..7165fa8
--- /dev/null
+++ b/internal/store/migrations/0024_hosts_always_on.sql
@@ -0,0 +1,6 @@
+-- 0024: distinguish always-on (24x7 server) hosts from intermittent
+-- hosts (laptops/workstations that legitimately sleep). Default 1 so
+-- every existing and future host keeps today's offline/alert
+-- semantics unless explicitly opted out. Column-level ALTER per the
+-- repo's migration rules (no table rebuild — hosts has inbound FKs).
+ALTER TABLE hosts ADD COLUMN always_on INTEGER NOT NULL DEFAULT 1;
diff --git a/internal/store/types.go b/internal/store/types.go
index cc60e48..9ad6326 100644
--- a/internal/store/types.go
+++ b/internal/store/types.go
@@ -99,6 +99,12 @@ type Host struct {
 	// agent-side message when RepoStatus == "init_failed".
 	RepoStatus      string
 	RepoStatusError string
+
+	// AlwaysOn is true for 24x7 server hosts (the default). When false
+	// the host is intermittent (laptop/workstation): offline alerts are
+	// suppressed, the UI shows an "asleep" state, and a missed backup is
+	// caught up ~1 min after reconnect. See the always-on-host-mode spec.
+	AlwaysOn bool
 }
 
 // Schedule is now intentionally slim: cron + which groups + enabled.