diff --git a/internal/repository/repository.go b/internal/repository/repository.go
index 625ad9b16..f41ce38a5 100644
--- a/internal/repository/repository.go
+++ b/internal/repository/repository.go
@@ -813,7 +813,14 @@ func (r *Repository) SaveBlob(ctx context.Context, t restic.BlobType, buf []byte
 
 	// compute plaintext hash if not already set
 	if id.IsNull() {
-		newID = restic.Hash(buf)
+		// Special case the hash calculation for all zero chunks. This is especially
+		// useful for sparse files containing large all zero regions. For these we can
+		// process chunks as fast as we can read the from disk.
+		if len(buf) == chunker.MinSize && restic.ZeroPrefixLen(buf) == chunker.MinSize {
+			newID = ZeroChunk()
+		} else {
+			newID = restic.Hash(buf)
+		}
 	} else {
 		newID = id
 	}
@@ -967,3 +974,14 @@ func streamPackPart(ctx context.Context, beLoad BackendLoadFn, key *crypto.Key,
 	})
 	return errors.Wrap(err, "StreamPack")
 }
+
+var zeroChunkOnce sync.Once
+var zeroChunkID restic.ID
+
+// ZeroChunk computes and returns (cached) the ID of an all-zero chunk with size chunker.MinSize
+func ZeroChunk() restic.ID {
+	zeroChunkOnce.Do(func() {
+		zeroChunkID = restic.Hash(make([]byte, chunker.MinSize))
+	})
+	return zeroChunkID
+}
diff --git a/internal/restorer/filerestorer.go b/internal/restorer/filerestorer.go
index 659458cd8..2deef1cd2 100644
--- a/internal/restorer/filerestorer.go
+++ b/internal/restorer/filerestorer.go
@@ -7,7 +7,6 @@ import (
 
 	"golang.org/x/sync/errgroup"
 
-	"github.com/restic/chunker"
 	"github.com/restic/restic/internal/crypto"
 	"github.com/restic/restic/internal/debug"
 	"github.com/restic/restic/internal/errors"
@@ -76,7 +75,7 @@ func newFileRestorer(dst string,
 		idx:         idx,
 		packLoader:  packLoader,
 		filesWriter: newFilesWriter(workerCount),
-		zeroChunk:   restic.Hash(make([]byte, chunker.MinSize)),
+		zeroChunk:   repository.ZeroChunk(),
 		sparse:      sparse,
 		workerCount: workerCount,
 		dst:         dst,