diff --git a/mailserver/mailserver.go b/mailserver/mailserver.go
index d87057024..c95e091dd 100644
--- a/mailserver/mailserver.go
+++ b/mailserver/mailserver.go
@@ -40,7 +40,10 @@ import (
 
 const (
 	maxQueryRange = 24 * time.Hour
-	noLimits      = 0
+	defaultLimit  = 2000
+	// When we default the upper limit, we want to extend the range a bit
+	// to accommodate for envelopes with slightly higher timestamp, in seconds
+	whisperTTLSafeThreshold = 60
 )
 
 var (
@@ -265,6 +268,10 @@ func (s *WMailServer) DeliverMail(peer *whisper.Peer, request *whisper.Envelope)
 		lower, upper, bloom, limit, cursor, err = s.validateRequest(peer.ID(), request)
 	}
 
+	if limit == 0 {
+		limit = defaultLimit
+	}
+
 	if err != nil {
 		requestValidationErrorsCounter.Inc(1)
 		log.Error("[mailserver:DeliverMail] request failed validaton",
@@ -535,7 +542,7 @@ func (s *WMailServer) processRequestInBundles(
 		lastEnvelopeHash = envelope.Hash()
 		processedEnvelopes++
 		envelopeSize := whisper.EnvelopeHeaderLength + uint32(len(envelope.Data))
-		limitReached := limit != noLimits && processedEnvelopes == limit
+		limitReached := processedEnvelopes == limit
 		newSize := bundleSize + envelopeSize
 
 		// If we still have some room for messages, add and continue
@@ -676,18 +683,15 @@ func (s *WMailServer) decodeRequest(peerID []byte, request *whisper.Envelope) (M
 		return payload, fmt.Errorf("failed to decode data: %v", err)
 	}
 
+	if payload.Upper == 0 {
+		payload.Upper = uint32(time.Now().Unix() + whisperTTLSafeThreshold)
+	}
+
 	if payload.Upper < payload.Lower {
 		log.Error("Query range is invalid: lower > upper", "lower", payload.Lower, "upper", payload.Upper)
 		return payload, errors.New("query range is invalid: lower > upper")
 	}
 
-	lowerTime := time.Unix(int64(payload.Lower), 0)
-	upperTime := time.Unix(int64(payload.Upper), 0)
-	if upperTime.Sub(lowerTime) > maxQueryRange {
-		log.Warn("Query range too long", "peerID", peerIDBytesString(peerID), "length", upperTime.Sub(lowerTime), "max", maxQueryRange)
-		return payload, fmt.Errorf("query range must be shorted than %d", maxQueryRange)
-	}
-
 	return payload, nil
 }
 
diff --git a/mailserver/mailserver_test.go b/mailserver/mailserver_test.go
index 1eb0520aa..8b6d814e7 100644
--- a/mailserver/mailserver_test.go
+++ b/mailserver/mailserver_test.go
@@ -467,6 +467,32 @@ func (s *MailserverSuite) TestDecodeRequest() {
 	s.Equal(payload, decodedPayload)
 }
 
+func (s *MailserverSuite) TestDecodeRequestNoUpper() {
+	s.setupServer(s.server)
+	defer s.server.Close()
+
+	payload := MessagesRequestPayload{
+		Lower:  50,
+		Bloom:  []byte{0x01},
+		Limit:  10,
+		Cursor: []byte{},
+		Batch:  true,
+	}
+	data, err := rlp.EncodeToBytes(payload)
+	s.Require().NoError(err)
+
+	id, err := s.shh.NewKeyPair()
+	s.Require().NoError(err)
+	srcKey, err := s.shh.GetPrivateKey(id)
+	s.Require().NoError(err)
+
+	env := s.createEnvelope(whisper.TopicType{0x01}, data, srcKey)
+
+	decodedPayload, err := s.server.decodeRequest(nil, env)
+	s.Require().NoError(err)
+	s.NotEqual(0, decodedPayload.Upper)
+}
+
 func (s *MailserverSuite) TestProcessRequestDeadlockHandling() {
 	s.setupServer(s.server)
 	defer s.server.Close()