diff --git a/cmd/restic/integration_test.go b/cmd/restic/integration_test.go
index 49121bb1d..ebf63e930 100644
--- a/cmd/restic/integration_test.go
+++ b/cmd/restic/integration_test.go
@@ -1470,7 +1470,7 @@ func TestRebuildIndexAlwaysFull(t *testing.T) {
 	defer func() {
 		repository.IndexFull = indexFull
 	}()
-	repository.IndexFull = func(*repository.Index) bool { return true }
+	repository.IndexFull = func(*repository.Index, bool) bool { return true }
 	testRebuildIndex(t, nil)
 }
 
diff --git a/internal/repository/index.go b/internal/repository/index.go
index 5f6fe1997..520fcbd8e 100644
--- a/internal/repository/index.go
+++ b/internal/repository/index.go
@@ -93,12 +93,13 @@ func (idx *Index) Final() bool {
 }
 
 const (
-	indexMaxBlobs = 50000
-	indexMaxAge   = 10 * time.Minute
+	indexMaxBlobs           = 50000
+	indexMaxBlobsCompressed = 3 * indexMaxBlobs
+	indexMaxAge             = 10 * time.Minute
 )
 
 // IndexFull returns true iff the index is "full enough" to be saved as a preliminary index.
-var IndexFull = func(idx *Index) bool {
+var IndexFull = func(idx *Index, compress bool) bool {
 	idx.m.Lock()
 	defer idx.m.Unlock()
 
@@ -109,12 +110,18 @@ var IndexFull = func(idx *Index) bool {
 		blobs += idx.byType[typ].len()
 	}
 	age := time.Since(idx.created)
+	var maxBlobs uint
+	if compress {
+		maxBlobs = indexMaxBlobsCompressed
+	} else {
+		maxBlobs = indexMaxBlobs
+	}
 
 	switch {
 	case age >= indexMaxAge:
 		debug.Log("index %p is old enough", idx, age)
 		return true
-	case blobs >= indexMaxBlobs:
+	case blobs >= maxBlobs:
 		debug.Log("index %p has %d blobs", idx, blobs)
 		return true
 	}
diff --git a/internal/repository/master_index.go b/internal/repository/master_index.go
index 9056528a2..96462d4a4 100644
--- a/internal/repository/master_index.go
+++ b/internal/repository/master_index.go
@@ -16,6 +16,7 @@ type MasterIndex struct {
 	idx          []*Index
 	pendingBlobs restic.BlobSet
 	idxMutex     sync.RWMutex
+	compress     bool
 }
 
 // NewMasterIndex creates a new master index.
@@ -28,6 +29,10 @@ func NewMasterIndex() *MasterIndex {
 	return &MasterIndex{idx: idx, pendingBlobs: restic.NewBlobSet()}
 }
 
+func (mi *MasterIndex) markCompressed() {
+	mi.compress = true
+}
+
 // Lookup queries all known Indexes for the ID and returns all matches.
 func (mi *MasterIndex) Lookup(bh restic.BlobHandle) (pbs []restic.PackedBlob) {
 	mi.idxMutex.RLock()
@@ -206,7 +211,7 @@ func (mi *MasterIndex) FinalizeFullIndexes() []*Index {
 			continue
 		}
 
-		if IndexFull(idx) {
+		if IndexFull(idx, mi.compress) {
 			debug.Log("index %p is full", idx)
 			idx.Finalize()
 			list = append(list, idx)
@@ -334,7 +339,7 @@ func (mi *MasterIndex) Save(ctx context.Context, repo restic.Repository, packBla
 			for pbs := range idx.EachByPack(ctx, packBlacklist) {
 				newIndex.StorePack(pbs.packID, pbs.blobs)
 				p.Add(1)
-				if IndexFull(newIndex) {
+				if IndexFull(newIndex, mi.compress) {
 					select {
 					case ch <- newIndex:
 					case <-ctx.Done():
diff --git a/internal/repository/repository.go b/internal/repository/repository.go
index f028b57ad..bbbc1af68 100644
--- a/internal/repository/repository.go
+++ b/internal/repository/repository.go
@@ -698,6 +698,9 @@ func (r *Repository) SearchKey(ctx context.Context, password string, maxKeys int
 	} else if err != nil {
 		return errors.Fatalf("config cannot be loaded: %v", err)
 	}
+	if r.Config().Version >= 2 {
+		r.idx.markCompressed()
+	}
 	return nil
 }
 
diff --git a/internal/repository/repository_test.go b/internal/repository/repository_test.go
index 7cc593e04..6da685ff3 100644
--- a/internal/repository/repository_test.go
+++ b/internal/repository/repository_test.go
@@ -367,7 +367,7 @@ func TestRepositoryIncrementalIndex(t *testing.T) {
 
 	repo := r.(*repository.Repository)
 
-	repository.IndexFull = func(*repository.Index) bool { return true }
+	repository.IndexFull = func(*repository.Index, bool) bool { return true }
 
 	// add 15 packs
 	for j := 0; j < 5; j++ {