diff --git a/src/action/UsageInterval.php b/src/action/UsageInterval.php
index 6b8693db..3251b8db 100644
--- a/src/action/UsageInterval.php
+++ b/src/action/UsageInterval.php
@@ -5,9 +5,10 @@
 use DateInterval;
 use DateTimeImmutable;
 use InvalidArgumentException;
+use JsonSerializable;
 
 /** @readonly */
-final class UsageInterval
+final class UsageInterval implements JsonSerializable
 {
     /** @readonly */
     private DateTimeImmutable $start;
@@ -189,4 +190,9 @@ public function extend(self $other): self
             $newEnd,
         );
     }
+
+    public function jsonSerialize(): array
+    {
+        return array_filter(get_object_vars($this));
+    }
 }
diff --git a/src/bill/BillCreationDto.php b/src/bill/BillCreationDto.php
index f93445f0..897ac8f2 100644
--- a/src/bill/BillCreationDto.php
+++ b/src/bill/BillCreationDto.php
@@ -36,4 +36,6 @@ class BillCreationDto
     public $charges;
 
     public $state;
+
+    public $usageInterval;
 }
diff --git a/src/bill/BillFactory.php b/src/bill/BillFactory.php
index aa89afd3..0f1a7d38 100644
--- a/src/bill/BillFactory.php
+++ b/src/bill/BillFactory.php
@@ -10,6 +10,10 @@
 
 namespace hiqdev\php\billing\bill;
 
+use DateTimeImmutable;
+use hiqdev\billing\hiapi\action\UsageIntervalHydrator;
+use hiqdev\php\billing\action\UsageInterval;
+
 /**
  * Default bill factory.
  *
@@ -23,7 +27,7 @@ class BillFactory implements BillFactoryInterface
      */
     public function create(BillCreationDto $dto)
     {
-        return new Bill(
+        $bill = new Bill(
             $dto->id,
             $dto->type,
             $dto->time,
@@ -35,5 +39,21 @@ public function create(BillCreationDto $dto)
             $dto->charges ?: [],
             $dto->state
         );
+        if (!empty($dto->usageInterval)) {
+            if ($dto->usageInterval instanceof UsageInterval) {
+                $interval = $dto->usageInterval;
+            } else {
+                $month = $dto->usageInterval['month']['date'];
+                $start = $dto->usageInterval['start']['date'];
+                $end = $dto->usageInterval['end']['date'];;
+                $interval = UsageInterval::withinMonth(
+                    new DateTimeImmutable($month),
+                    new DateTimeImmutable($start),
+                    new DateTimeImmutable($end)
+                );
+            }
+            $bill->setUsageInterval($interval);
+        }
+        return $bill;
     }
 }
diff --git a/src/tools/Merger.php b/src/tools/Merger.php
index ab61b843..693d3c9a 100644
--- a/src/tools/Merger.php
+++ b/src/tools/Merger.php
@@ -46,7 +46,7 @@ public function mergeBill(BillInterface $first, BillInterface $other): BillInter
     {
         $charges = $this->mergeCharges(array_merge($first->getCharges(), $other->getCharges()));
 
-        return new Bill(
+        $bill = new Bill(
             $this->mergeId($first, $other),
             $first->getType(),
             $first->getTime(),
@@ -57,6 +57,8 @@ public function mergeBill(BillInterface $first, BillInterface $other): BillInter
             $first->getPlan(),
             $charges
         );
+        $bill->setUsageInterval($first->getUsageInterval());
+        return $bill;
     }
 
     /**
diff --git a/tests/behat/bootstrap/BillingContext.php b/tests/behat/bootstrap/BillingContext.php
index a94600d3..1e335e56 100644
--- a/tests/behat/bootstrap/BillingContext.php
+++ b/tests/behat/bootstrap/BillingContext.php
@@ -300,6 +300,36 @@ public function billWithTime($type, $sum, $currency, $quantity, $unit, $target,
         }
     }
 
+    /**
+     * @Given /bill interval +for (\S+) is +(\S+) (\S+) per (\S+) (\S+) for target (.+?) at (\S+) between (\S+) and (\S+)?$/
+     */
+    public function billInterval($type, $sum, $currency, $quantity, $unit, $target, $time, $since, $till)
+    {
+        $this->builder->flushEntitiesCacheByType('bill');
+
+        $quantity = $this->prepareQuantity($quantity);
+        $sum = $this->prepareSum($sum, $quantity);
+        $time = $this->prepareTime($time);
+        $bill = $this->findBill([
+            'type' => $type,
+            'target' => $target,
+            'sum' => "$sum $currency",
+            'quantity' => "$quantity $unit",
+            'time' => $time,
+        ]);
+        Assert::assertSame($type, $bill->getType()->getName(), "Bill type mismatch: expected $type, got {$bill->getType()->getName()}");
+        Assert::assertSame($target, $bill->getTarget()->getFullName(), "Bill target mismatch: expected $target, got {$bill->getTarget()->getFullName()}");
+        Assert::assertEquals(bcmul($sum, 100), $bill->getSum()->getAmount(), "Bill sum mismatch: expected $sum, got {$bill->getSum()->getAmount()}");
+        Assert::assertSame($currency, $bill->getSum()->getCurrency()->getCode(), "Bill currency mismatch: expected $currency, got {$bill->getSum()->getCurrency()->getCode()}");
+        Assert::assertEquals((float)$quantity, (float)$bill->getQuantity()->getQuantity(), "Bill quantity mismatch: expected $quantity, got {$bill->getQuantity()->getQuantity()}");
+        Assert::assertEquals(strtolower($unit), strtolower($bill->getQuantity()->getUnit()->getName()), "Bill unit mismatch: expected $unit, got {$bill->getQuantity()->getUnit()->getName()}");
+        Assert::assertEquals(new DateTimeImmutable($time), $bill->getTime(), "Bill time mismatch: expected $time, got {$bill->getTime()->format(DATE_ATOM)}");
+        $billStart = $bill->getUsageInterval()->start();
+        $billEnd = $bill->getUsageInterval()->end();
+        Assert::assertEquals(new DateTimeImmutable($since), $billStart, "Bill since time mismatch: expected $since, got {$billStart->format(DATE_ATOM)}");
+        Assert::assertEquals(new DateTimeImmutable($till), $billEnd, "Bill till time mismatch: expected $till, got {$billEnd->format(DATE_ATOM)}");
+    }
+
     public function findBill(array $params): BillInterface
     {
         $bills = $this->builder->findBills($params);