diff --git a/app/models/alaveteli_pro/invoice_collection.rb b/app/models/alaveteli_pro/invoice_collection.rb
index b1f00882e3..8e60b107a3 100644
--- a/app/models/alaveteli_pro/invoice_collection.rb
+++ b/app/models/alaveteli_pro/invoice_collection.rb
@@ -52,7 +52,7 @@ def each(&block)
     def invoices
       return [] unless @customer
 
-      @invoices ||= Stripe::Invoice.list(customer: @customer)
+      @invoices ||= Stripe::Invoice.list(customer: @customer.id)
     end
   end
 end
diff --git a/spec/models/alaveteli_pro/invoice_collection_spec.rb b/spec/models/alaveteli_pro/invoice_collection_spec.rb
new file mode 100644
index 0000000000..dbfe81d226
--- /dev/null
+++ b/spec/models/alaveteli_pro/invoice_collection_spec.rb
@@ -0,0 +1,128 @@
+require 'spec_helper'
+require 'stripe_mock'
+
+RSpec.describe AlaveteliPro::InvoiceCollection do
+  let(:collection) { described_class.new(customer) }
+  let(:customer) { double(:customer, id: 'cus_123') }
+
+  let(:open_invoice) { double(:invoice, status: 'open') }
+  let(:paid_invoice) { double(:invoice, status: 'paid', amount_paid: 10) }
+
+  describe '.for_customer' do
+    it 'should return instance for customer' do
+      collection = described_class.for_customer(customer)
+      expect(collection).to be_a described_class
+    end
+
+    it 'should pass customer to instance' do
+      expect(described_class).to receive(:new).with(customer)
+      described_class.for_customer(customer)
+    end
+  end
+
+  describe '.new' do
+    it 'should store customer instance variable' do
+      expect(collection.instance_variable_get(:@customer)).to eq customer
+    end
+  end
+
+  describe '#retrieve' do
+    context 'without customer' do
+      let(:customer) { nil }
+
+      it 'returns nil' do
+        expect(collection.retrieve(123)).to eq nil
+      end
+    end
+
+    context 'with Stripe invoices' do
+      let(:invoices) { Stripe::ListObject.new }
+
+      before do
+        allow(Stripe::Invoice).to receive(:list).with(customer: 'cus_123').
+          and_return(invoices)
+      end
+
+      it 'should retrieve wrapped invoice' do
+        invoice = double('Stripe::Invoice')
+        allow(invoices).to receive(:retrieve).with(123).
+          and_return(invoice)
+        expect(collection.retrieve(123)).to be_a AlaveteliPro::Invoice
+        expect(collection.retrieve(123)).to eq invoice
+      end
+    end
+  end
+
+  describe '#open' do
+    before do
+      allow(Stripe::Invoice).to receive(:list).with(customer: 'cus_123').
+        and_return([open_invoice, paid_invoice])
+    end
+
+    it 'should return any open invoice' do
+      expect(collection.open).to match_array([open_invoice])
+    end
+  end
+
+  describe '#paid' do
+    before do
+      allow(Stripe::Invoice).to receive(:list).with(customer: 'cus_123').
+        and_return([open_invoice, paid_invoice])
+    end
+
+    it 'should return any paid invoice' do
+      expect(collection.paid).to match_array([paid_invoice])
+    end
+  end
+
+  describe '#each' do
+    context 'without customer' do
+      let(:customer) { nil }
+
+      it 'returns no invoices' do
+        expect(collection.count).to eq 0
+      end
+    end
+
+    context 'with Stripe invoices' do
+      let(:invoices) { Stripe::ListObject.new }
+
+      before do
+        allow(Stripe::Invoice).to receive(:list).with(customer: 'cus_123').
+          and_return(invoices)
+        allow(invoices).to receive(:auto_paging_each).
+          and_yield(open_invoice).
+          and_yield(paid_invoice)
+      end
+
+      it 'returns to correct amount of objects' do
+        expect(collection.count).to eq 2
+      end
+
+      it 'wraps invoices as AlaveteliPro::Invoice objects' do
+        expect(collection.to_a).to all(be_a AlaveteliPro::Invoice)
+      end
+    end
+
+    context 'without Stripe invoices' do
+      before do
+        allow(Stripe::Invoice).to receive(:list).with(customer: 'cus_123').
+          and_return([open_invoice, paid_invoice, open_invoice])
+      end
+
+      it 'returns to correct amount of objects' do
+        expect(collection.count).to eq 3
+      end
+
+      it 'wraps invoices as AlaveteliPro::Invoice objects' do
+        expect(collection.to_a).to all(be_a AlaveteliPro::Invoice)
+      end
+    end
+
+    context 'without block' do
+      it 'should return a Enumerator' do
+        expect(collection.each).to be_a Enumerator
+      end
+    end
+  end
+end