diff --git a/promql/engine.go b/promql/engine.go
index b73364bc87..5757604b7a 100644
--- a/promql/engine.go
+++ b/promql/engine.go
@@ -1367,18 +1367,6 @@ func (ev *evaluator) rangeEvalAgg(aggExpr *parser.AggregateExpr, sortedGrouping
 		enh.Out = result[:0] // Reuse result vector.
 		warnings.Merge(ws)
 
-		vecNumSamples := result.TotalSamples()
-		ev.currentSamples += vecNumSamples
-		// When we reset currentSamples to tempNumSamples during the next iteration of the loop it also
-		// needs to include the samples from the result here, as they're still in memory.
-		tempNumSamples += vecNumSamples
-		ev.samplesStats.UpdatePeak(ev.currentSamples)
-
-		if ev.currentSamples > ev.maxSamples {
-			ev.error(ErrTooManySamples(env))
-		}
-		ev.samplesStats.UpdatePeak(ev.currentSamples)
-
 		// If this could be an instant query, shortcut so as not to change sort order.
 		if ev.endTimestamp == ev.startTimestamp {
 			mat := make(Matrix, len(result))
@@ -1393,6 +1381,9 @@ func (ev *evaluator) rangeEvalAgg(aggExpr *parser.AggregateExpr, sortedGrouping
 			ev.samplesStats.UpdatePeak(ev.currentSamples)
 			return mat, warnings
 		}
+		if ev.currentSamples > ev.maxSamples {
+			ev.error(ErrTooManySamples(env))
+		}
 	}
 
 	// Reuse the original point slice.
@@ -2946,7 +2937,33 @@ func (ev *evaluator) aggregation(e *parser.AggregateExpr, grouping []string, par
 		}
 	}
 
-	// Construct the result Vector from the aggregated groups.
+	// Construct the result from the aggregated groups.
+	numSteps := int((ev.endTimestamp-ev.startTimestamp)/ev.interval) + 1
+	add := func(lbls labels.Labels, f float64, h *histogram.FloatHistogram) {
+		// If this could be an instant query, build a slice so the result is in consistent order.
+		if ev.endTimestamp == ev.startTimestamp {
+			enh.Out = append(enh.Out, Sample{Metric: lbls, F: f, H: h})
+		} else {
+			// Otherwise the results are added into seriess elements.
+			hash := lbls.Hash()
+			ss, ok := seriess[hash]
+			if !ok {
+				ss = Series{Metric: lbls}
+			}
+			if h == nil {
+				if ss.Floats == nil {
+					ss.Floats = getFPointSlice(numSteps)
+				}
+				ss.Floats = append(ss.Floats, FPoint{T: enh.Ts, F: f})
+			} else {
+				if ss.Histograms == nil {
+					ss.Histograms = getHPointSlice(numSteps)
+				}
+				ss.Histograms = append(ss.Histograms, HPoint{T: enh.Ts, H: h})
+			}
+			seriess[hash] = ss
+		}
+	}
 	for _, aggr := range orderedResult {
 		switch op {
 		case parser.AVG:
@@ -2976,10 +2993,7 @@ func (ev *evaluator) aggregation(e *parser.AggregateExpr, grouping []string, par
 				sort.Sort(sort.Reverse(aggr.heap))
 			}
 			for _, v := range aggr.heap {
-				enh.Out = append(enh.Out, Sample{
-					Metric: v.Metric,
-					F:      v.F,
-				})
+				add(v.Metric, v.F, nil)
 			}
 			continue // Bypass default append.
 
@@ -2989,10 +3003,7 @@ func (ev *evaluator) aggregation(e *parser.AggregateExpr, grouping []string, par
 				sort.Sort(sort.Reverse(aggr.reverseHeap))
 			}
 			for _, v := range aggr.reverseHeap {
-				enh.Out = append(enh.Out, Sample{
-					Metric: v.Metric,
-					F:      v.F,
-				})
+				add(v.Metric, v.F, nil)
 			}
 			continue // Bypass default append.
 
@@ -3015,42 +3026,10 @@ func (ev *evaluator) aggregation(e *parser.AggregateExpr, grouping []string, par
 			// For other aggregations, we already have the right value.
 		}
 
-		enh.Out = append(enh.Out, Sample{
-			Metric: aggr.labels,
-			F:      aggr.floatValue,
-			H:      aggr.histogramValue,
-		})
+		add(aggr.labels, aggr.floatValue, aggr.histogramValue)
 	}
 
-	ts := enh.Ts
-	// If this could be an instant query, shortcut so as not to change sort order.
-	if ev.endTimestamp == ev.startTimestamp {
-		return enh.Out, annos
-	}
-
-	numSteps := int((ev.endTimestamp-ev.startTimestamp)/ev.interval) + 1
-	// Add samples in output vector to output series.
-	for _, sample := range enh.Out {
-		h := sample.Metric.Hash()
-		ss, ok := seriess[h]
-		if !ok {
-			ss = Series{Metric: sample.Metric}
-		}
-		if sample.H == nil {
-			if ss.Floats == nil {
-				ss.Floats = getFPointSlice(numSteps)
-			}
-			ss.Floats = append(ss.Floats, FPoint{T: ts, F: sample.F})
-		} else {
-			if ss.Histograms == nil {
-				ss.Histograms = getHPointSlice(numSteps)
-			}
-			ss.Histograms = append(ss.Histograms, HPoint{T: ts, H: sample.H})
-		}
-		seriess[h] = ss
-	}
-
-	return nil, annos
+	return enh.Out, annos
 }
 
 // aggregationK evaluates count_values on vec.
diff --git a/promql/engine_test.go b/promql/engine_test.go
index 13731efd45..0202c15ae1 100644
--- a/promql/engine_test.go
+++ b/promql/engine_test.go
@@ -966,7 +966,7 @@ load 10s
 		{
 			Query:        "sum by (b) (max_over_time(metricWith3SampleEvery10Seconds[60s] @ 30))",
 			Start:        time.Unix(201, 0),
-			PeakSamples:  8,
+			PeakSamples:  7,
 			TotalSamples: 12, // @ modifier force the evaluation to at 30 seconds - So it brings 4 datapoints (0, 10, 20, 30 seconds) * 3 series
 			TotalSamplesPerStep: stats.TotalSamplesPerStep{
 				201000: 12,