diff --git a/repo/content/committed_content_index.go b/repo/content/committed_content_index.go
index 6b54e0b24..32ef8f454 100644
--- a/repo/content/committed_content_index.go
+++ b/repo/content/committed_content_index.go
@@ -1,6 +1,7 @@
 package content
 
 import (
+	"bytes"
 	"context"
 	"path/filepath"
 	"sync"
@@ -10,6 +11,12 @@
 	"github.com/kopia/kopia/repo/blob"
 )
 
+// smallIndexEntryCountThreshold is the threshold to determine whether an
+// index is small. Any index with fewer entries than this threshold
+// will be combined in-memory to reduce the number of segments and speed up
+// large index operations (such as verification of all contents).
+const smallIndexEntryCountThreshold = 100
+
 type committedContentIndex struct {
 	cache committedContentIndexCache
 
@@ -119,7 +126,14 @@ func (b *committedContentIndex) use(ctx context.Context, packFiles []blob.ID) (b
 		newInUse[e] = ndx
 	}
 
-	b.merged = newMerged
+	mergedAndCombined, err := combineSmallIndexes(newMerged)
+	if err != nil {
+		return false, errors.Wrap(err, "unable to combine small indexes")
+	}
+
+	log(ctx).Debugf("combined %v into %v index segments", len(newMerged), len(mergedAndCombined))
+
+	b.merged = mergedAndCombined
 	b.inUse = newInUse
 
 	if err := b.cache.expireUnused(ctx, packFiles); err != nil {
@@ -131,6 +145,46 @@ func (b *committedContentIndex) use(ctx context.Context, packFiles []blob.ID) (b
 	return true, nil
 }
 
+func combineSmallIndexes(m mergedIndex) (mergedIndex, error) {
+	var toKeep, toMerge mergedIndex
+
+	for _, ndx := range m {
+		if ndx.ApproximateCount() < smallIndexEntryCountThreshold {
+			toMerge = append(toMerge, ndx)
+		} else {
+			toKeep = append(toKeep, ndx)
+		}
+	}
+
+	if len(toMerge) <= 1 {
+		return m, nil
+	}
+
+	b := packIndexBuilder{}
+
+	for _, ndx := range toMerge {
+		if err := ndx.Iterate(AllIDs, func(i Info) error {
+			b.Add(i)
+			return nil
+		}); err != nil {
+			return nil, errors.Wrap(err, "unable to iterate index entries")
+		}
+	}
+
+	var buf bytes.Buffer
+
+	if err := b.Build(&buf); err != nil {
+		return nil, errors.Wrap(err, "error building combined in-memory index")
+	}
+
+	combined, err := openPackIndex(bytes.NewReader(buf.Bytes()))
+	if err != nil {
+		return nil, errors.Wrap(err, "error opening combined in-memory index")
+	}
+
+	return append(toKeep, combined), nil
+}
+
 func (b *committedContentIndex) close() error {
 	b.mu.Lock()
 	defer b.mu.Unlock()
diff --git a/repo/content/index.go b/repo/content/index.go
index a69ec45e1..ab3331ede 100644
--- a/repo/content/index.go
+++ b/repo/content/index.go
@@ -21,6 +21,8 @@
 type packIndex interface {
 	io.Closer
 
+	ApproximateCount() int
+
 	GetInfo(contentID ID) (*Info, error)
 
 	// invoked the provided callback for all entries such that entry.ID >= startID and entry.ID < endID
@@ -89,6 +91,10 @@ func readHeader(readerAt io.ReaderAt) (headerInfo, error) {
 	return hi, nil
 }
 
+func (b *index) ApproximateCount() int {
+	return b.hdr.entryCount
+}
+
 // Iterate invokes the provided callback function for a range of contents in the index, sorted alphabetically.
 // The iteration ends when the callback returns an error, which is propagated to the caller or when
 // all contents have been visited.
diff --git a/repo/content/merged.go b/repo/content/merged.go
index d455be999..2ac7230f8 100644
--- a/repo/content/merged.go
+++ b/repo/content/merged.go
@@ -11,6 +11,16 @@
 // mergedIndex is an implementation of Index that transparently merges returns from underlying Indexes.
 type mergedIndex []packIndex
 
+func (m mergedIndex) ApproximateCount() int {
+	c := 0
+
+	for _, ndx := range m {
+		c += ndx.ApproximateCount()
+	}
+
+	return c
+}
+
 // Close closes all underlying indexes.
 func (m mergedIndex) Close() error {
 	for _, ndx := range m {