diff --git a/engine/callcost.go b/engine/callcost.go
index e786318a7..98984333c 100644
--- a/engine/callcost.go
+++ b/engine/callcost.go
@@ -162,13 +162,19 @@ func (cc *CallCost) AsJSON() string {
 	return utils.ToJSON(cc)
 }
 
+// public function to update final (merged) callcost
+func (cc *CallCost) UpdateCost() {
+	cc.deductConnectFee = true
+	cc.updateCost()
+}
+
 func (cc *CallCost) updateCost() {
 	cost := 0.0
 	if cc.deductConnectFee { // add back the connectFee
 		cost += cc.GetConnectFee()
 	}
 	for _, ts := range cc.Timespans {
-		ts.Cost = ts.calculateCost()
+		ts.Cost = ts.CalculateCost()
 		cost += ts.Cost
 		cost = utils.Round(cost, globalRoundingDecimals, utils.ROUNDING_MIDDLE) // just get rid of the extra decimals
 	}
diff --git a/engine/calldesc.go b/engine/calldesc.go
index 051d98940..2ead17ea5 100644
--- a/engine/calldesc.go
+++ b/engine/calldesc.go
@@ -458,7 +458,7 @@ func (cd *CallDescriptor) GetCost() (*CallCost, error) {
 		// handle max cost
 		maxCost, strategy := ts.RateInterval.GetMaxCost()
 
-		ts.Cost = ts.calculateCost()
+		ts.Cost = ts.CalculateCost()
 		cost += ts.Cost
 		cd.MaxCostSoFar += cost
 		//log.Print("Before: ", cost)
@@ -517,7 +517,7 @@ func (cd *CallDescriptor) getCost() (*CallCost, error) {
 		if cd.LoopIndex == 0 && i == 0 && ts.RateInterval != nil {
 			cost += ts.RateInterval.Rating.ConnectFee
 		}
-		cost += ts.calculateCost()
+		cost += ts.CalculateCost()
 	}
 
 	//startIndex := len(fmt.Sprintf("%s:%s:%s:", cd.Direction, cd.Tenant, cd.Category))
diff --git a/engine/cdrs.go b/engine/cdrs.go
index b522b829c..f4a5b0714 100644
--- a/engine/cdrs.go
+++ b/engine/cdrs.go
@@ -108,6 +108,7 @@ func (self *CdrServer) ProcessExternalCdr(eCDR *ExternalCDR) error {
 
 // RPC method, used to log callcosts to db
 func (self *CdrServer) LogCallCost(ccl *CallCostLog) error {
+	ccl.CallCost.UpdateCost()       // make sure the total cost reflect the increments
 	ccl.CallCost.UpdateRatedUsage() // make sure rated usage is updated
 	if ccl.CheckDuplicate {
 		_, err := self.guard.Guard(func() (interface{}, error) {
@@ -177,6 +178,7 @@ func (self *CdrServer) processCdr(cdr *CDR) (err error) {
 	}
 	if self.cgrCfg.CDRSStoreCdrs { // Store RawCDRs, this we do sync so we can reply with the status
 		if cdr.CostDetails != nil {
+			cdr.CostDetails.UpdateCost()
 			cdr.CostDetails.UpdateRatedUsage()
 		}
 		if err := self.cdrDb.SetCDR(cdr, false); err != nil { // Only original CDR stored in primary table, no derived
@@ -236,6 +238,7 @@ func (self *CdrServer) rateStoreStatsReplicate(cdr *CDR, sendToStats bool) error
 	if self.cgrCfg.CDRSStoreCdrs { // Store CDRs
 		// Store RatedCDR
 		if cdr.CostDetails != nil {
+			cdr.CostDetails.UpdateCost()
 			cdr.CostDetails.UpdateRatedUsage()
 		}
 		if err := self.cdrDb.SetCDR(cdr, true); err != nil {
diff --git a/engine/timespans.go b/engine/timespans.go
index b89739552..b7f530d59 100644
--- a/engine/timespans.go
+++ b/engine/timespans.go
@@ -280,7 +280,7 @@ func (incs Increments) GetTotalCost() float64 {
 	for _, increment := range incs {
 		cost += increment.GetCost()
 	}
-	return cost
+	return utils.Round(cost, globalRoundingDecimals, utils.ROUNDING_MIDDLE)
 }
 
 func (incs Increments) Length() (length int) {
@@ -321,15 +321,14 @@ func (ts *TimeSpan) SetRateInterval(interval *RateInterval) {
 // Returns the cost of the timespan according to the relevant cost interval.
 // It also sets the Cost field of this timespan (used for refund on session
 // manager debit loop where the cost cannot be recalculated)
-func (ts *TimeSpan) calculateCost() float64 {
+func (ts *TimeSpan) CalculateCost() float64 {
 	if ts.Increments.Length() == 0 {
 		if ts.RateInterval == nil {
 			return 0
 		}
 		return ts.RateInterval.GetCost(ts.GetDuration(), ts.GetGroupStart())
 	} else {
-		cost := ts.Increments.GetTotalCost()
-		return utils.Round(cost, globalRoundingDecimals, utils.ROUNDING_MIDDLE)
+		return ts.Increments.GetTotalCost()
 	}
 }
 
@@ -352,7 +351,7 @@ func (ts *TimeSpan) createIncrementsSlice() {
 	// because ts cost is rounded
 	//incrementCost := rate / rateUnit.Seconds() * rateIncrement.Seconds()
 	nbIncrements := int(ts.GetDuration() / rateIncrement)
-	incrementCost := ts.calculateCost() / float64(nbIncrements)
+	incrementCost := ts.CalculateCost() / float64(nbIncrements)
 	incrementCost = utils.Round(incrementCost, ts.RateInterval.Rating.RoundingDecimals, ts.RateInterval.Rating.RoundingMethod)
 	for s := 0; s < nbIncrements; s++ {
 		inc := &Increment{
diff --git a/engine/timespans_test.go b/engine/timespans_test.go
index 47b64315d..225cba090 100644
--- a/engine/timespans_test.go
+++ b/engine/timespans_test.go
@@ -214,7 +214,7 @@ func TestTSTimespanGetCost(t *testing.T) {
 	t1 := time.Date(2012, time.February, 5, 17, 45, 0, 0, time.UTC)
 	t2 := time.Date(2012, time.February, 5, 17, 55, 0, 0, time.UTC)
 	ts1 := TimeSpan{TimeStart: t1, TimeEnd: t2}
-	if ts1.calculateCost() != 0 {
+	if ts1.CalculateCost() != 0 {
 		t.Error("No interval and still kicking")
 	}
 	ts1.SetRateInterval(
@@ -223,12 +223,12 @@ func TestTSTimespanGetCost(t *testing.T) {
 			Rating: &RIRate{Rates: RateGroups{&Rate{0, 1.0, 1 * time.Second, 1 * time.Second}}},
 		},
 	)
-	if ts1.calculateCost() != 600 {
+	if ts1.CalculateCost() != 600 {
 		t.Error("Expected 10 got ", ts1.Cost)
 	}
 	ts1.RateInterval = nil
 	ts1.SetRateInterval(&RateInterval{Rating: &RIRate{Rates: RateGroups{&Rate{0, 1.0, 1 * time.Second, 60 * time.Second}}}})
-	if ts1.calculateCost() != 10 {
+	if ts1.CalculateCost() != 10 {
 		t.Error("Expected 6000 got ", ts1.Cost)
 	}
 }
@@ -239,8 +239,8 @@ func TestTSTimespanGetCostIntervals(t *testing.T) {
 	for i := 0; i < 11; i++ {
 		ts.Increments[i] = &Increment{Cost: 0.02}
 	}
-	if ts.calculateCost() != 0.22 {
-		t.Error("Error caclulating timespan cost: ", ts.calculateCost())
+	if ts.CalculateCost() != 0.22 {
+		t.Error("Error caclulating timespan cost: ", ts.CalculateCost())
 	}
 }
 
diff --git a/sessionmanager/session.go b/sessionmanager/session.go
index 061ea84ca..91fb952d2 100644
--- a/sessionmanager/session.go
+++ b/sessionmanager/session.go
@@ -180,6 +180,7 @@ func (s *Session) Refund(lastCC *engine.CallCost, hangupTime time.Time) error {
 				lastCC.Timespans = lastCC.Timespans[:i]
 			} else {
 				ts.SplitByIncrement(lastRefundedIncrementIndex)
+				ts.Cost = ts.CalculateCost()
 			}
 			break // do not go to other timespans
 		} else {
@@ -214,6 +215,7 @@ func (s *Session) Refund(lastCC *engine.CallCost, hangupTime time.Time) error {
 	}
 	//utils.Logger.Debug(fmt.Sprintf("REFUND INCR: %s", utils.ToJSON(refundIncrements)))
 	lastCC.Cost -= refundIncrements.GetTotalCost()
+	lastCC.UpdateRatedUsage()
 	lastCC.Timespans.Compress()
 	return nil
 }
diff --git a/sessionmanager/smg_session.go b/sessionmanager/smg_session.go
index 18a86a9b5..d097b91e5 100644
--- a/sessionmanager/smg_session.go
+++ b/sessionmanager/smg_session.go
@@ -132,6 +132,7 @@ func (self *SMGSession) refund(refundDuration time.Duration) error {
 				lastCC.Timespans = lastCC.Timespans[:i]
 			} else {
 				ts.SplitByIncrement(lastRefundedIncrementIndex)
+				ts.Cost = ts.CalculateCost()
 			}
 			break // do not go to other timespans
 		} else {
@@ -166,6 +167,7 @@ func (self *SMGSession) refund(refundDuration time.Duration) error {
 	}
 	//utils.Logger.Debug(fmt.Sprintf("REFUND INCR: %s", utils.ToJSON(refundIncrements)))
 	lastCC.Cost -= refundIncrements.GetTotalCost()
+	lastCC.UpdateRatedUsage()
 	lastCC.Timespans.Compress()
 	return nil
 }