diff --git a/pkg/kgo/source.go b/pkg/kgo/source.go
index 4b9a8f20..3d6ef59d 100644
--- a/pkg/kgo/source.go
+++ b/pkg/kgo/source.go
@@ -1496,6 +1496,9 @@ type fetchRequest struct {
 	numOffsets  int
 	usedOffsets usedOffsets
 
+	torder []string           // order of topics to write
+	porder map[string][]int32 // per topic, order of partitions to write
+
 	topic2id map[string][16]byte
 	id2topic map[[16]byte]string
 
@@ -1510,6 +1513,7 @@ func (f *fetchRequest) addCursor(c *cursor) {
 		f.usedOffsets = make(usedOffsets)
 		f.id2topic = make(map[[16]byte]string)
 		f.topic2id = make(map[string][16]byte)
+		f.porder = make(map[string][]int32)
 	}
 	partitions := f.usedOffsets[c.topic]
 	if partitions == nil {
@@ -1517,8 +1521,10 @@ func (f *fetchRequest) addCursor(c *cursor) {
 		f.usedOffsets[c.topic] = partitions
 		f.id2topic[c.topicID] = c.topic
 		f.topic2id[c.topic] = c.topicID
+		f.torder = append(f.torder, c.topic)
 	}
 	partitions[c.partition] = c.use()
+	f.porder[c.topic] = append(f.porder[c.topic], c.partition)
 	f.numOffsets++
 }
 
@@ -1547,7 +1553,8 @@ func (f *fetchRequest) AppendTo(dst []byte) []byte {
 		sessionUsed = make(map[string]map[int32]struct{}, len(f.usedOffsets))
 	}
 
-	for topic, partitions := range f.usedOffsets {
+	for _, topic := range f.torder {
+		partitions := f.usedOffsets[topic]
 
 		var reqTopic *kmsg.FetchRequestTopic
 		sessionTopic := f.session.lookupTopic(topic)
@@ -1557,7 +1564,8 @@ func (f *fetchRequest) AppendTo(dst []byte) []byte {
 			usedTopic = make(map[int32]struct{}, len(partitions))
 		}
 
-		for partition, cursorOffsetNext := range partitions {
+		for _, partition := range f.porder[topic] {
+			cursorOffsetNext := partitions[partition]
 
 			if usedTopic != nil {
 				usedTopic[partition] = struct{}{}