diff --git a/mail_templates/beitrag.eml b/mail_templates/beitrag.eml
new file mode 100644
index 0000000..f853b8a
--- /dev/null
+++ b/mail_templates/beitrag.eml
@@ -0,0 +1,31 @@
+Hallo {{ invoice.party.name }},
+
+für deine ordentliche Mitgliedschaft im Chaos Computer Club Bremen e.V. ist ein Mitgliedsbeitrag fällig.  Für das Beitragsjahr {{ year.year }} beträgt der monatliche Beitrag {{ monthly_fee }} €.  Dieser Beitrag ist jeweils zu Beginn des Monats fällig.
+
+Wir berechnen dir daher die folgenden Mitgliedsbeiträge:
+{% for line in invoice.lines %}
+{{ line.description.ljust(50) }} {{ "{: >.2f}".format(line.unit_price) }} €
+{%- endfor %}
+
+{% if sepa_mandate -%}
+Wir werden deine Mitgliedsbeiträge per SEPA-Lastschrift von deinem Konto mit der IBAN {{ sepa_mandate.account_number.number }} zu den folgenden Terminen einziehen:
+
+{% for payment in invoice.lines_to_pay if not payment.reconiciliation and payment.payable_receivable_balance %}
+{{ payment.maturity_date }}      {{ "{: >.2f}".format(payment.amount) }} €
+{%- endfor %}
+{% else -%}
+Bitte überweise deine Mitgliedsbeiträge fristgerecht auf unser Konto:
+
+Kontoinhaber: Chaos Computer Club Bremen e.V.
+IBAN: DE28 4306 0967 2027 5271 00
+Bank: GLS Gemeinschaftsbank eG
+BIC: GENODEM1GLS
+Verwendungszweck: Beitrag {{ invoice.party.name }}
+
+Du kannst den Beitrag für das gesamte Jahr {{ year.year }} im Voraus überweisen.
+{%- endif %}
+
+Viele Grüße,
+der Vorstand
+
+i.A. {{ sender }}
diff --git a/mail_templates/sepa_mandat.eml b/mail_templates/sepa_mandat.eml
new file mode 100644
index 0000000..3ed1b80
--- /dev/null
+++ b/mail_templates/sepa_mandat.eml
@@ -0,0 +1,21 @@
+Hallo {{ party.name }},
+
+anbei erhälst du eine Abschrift des SEPA-Lastschriftmandats mit der Mandatsreferenz „{{ sepa_mandate.identification }}“, das zum Einzug deiner Mitgliedsbeiträge bei uns gespeichert ist.
+
+Name des Zahlungsempfängers:
+    Chaos Computer Club Bremen e.V.
+Anschrift des Zahlungsempfängers:
+    Konsul-Smidt-Straße 43, 28217 Bremen, Deutschland
+Gläubiger-Identifikationsnummer:
+    DE20 CCC0 0000 9634 98
+
+Kontoinhaber*in:          {{ sepa_mandate.party.name }}
+IBAN der Kontoinhaber*in: {{ sepa_mandate.account_number.number }}
+Mandatsreferenz:          {{ sepa_mandate.identification }}
+Zahlungsart:              Wiederkehrende Zahlung
+Datum:                    {{ sepa_mandate.signature_date }}
+
+Sollten Angaben in diesem Mandat fehlerhaft oder veraltet sein, so teil uns dies bitte per E-Mail an vorstand@ccchb.de mit.
+
+Viele Grüße,
+der Vorstand des Chaos Computer Club Bremen e.V.
diff --git a/sepa-mandate/reify.py b/sepa-mandate/reify.py
deleted file mode 100644
index 3259a30..0000000
--- a/sepa-mandate/reify.py
+++ /dev/null
@@ -1,99 +0,0 @@
-#!/bin/env python3
-
-import csv
-import subprocess
-import email.message
-import email.utils
-import datetime
-import argparse
-import pathlib
-import tempfile
-import shutil
-
-DEFAULT_CSV_FIELDLIST = ("creditor_name", "creditor_iban", "mandate", "recurrence", "date", "email")
-
-def create_tex(mandate):
-    return f'''
-\csdef{{sepa-m001}}{{{mandate['mandate']}}}
-\csdef{{sepa-m006}}{{{mandate['recurrence']}}}
-\csdef{{sepa-p001}}{{{mandate['creditor_name']}}}
-\csdef{{sepa-d001}}{{{mandate['creditor_iban']}}}
-\csdef{{sepa-m008}}{{{mandate['date']}}}
-\csdef{{sepa-m009}}{{\emph{{entfällt}}}}
-\csdef{{sepa-d002a}}{{}}
-\csdef{{sepa-d002b}}{{}}
-\csdef{{sepa-p005}}{{}}
-\csdef{{sepa-remarks}}{{Dieses Mandat ist eine Abschrift des dem Zahlungsempfänger vorliegenden, originalen SEPA-Lastschriftmandats.\\\\
-Erstellt am {datetime.date.today()}}}
-'''
-
-EMAIL_MESSAGE = """Liebes Mitglied,
-
-anbei erhälst du eine Abschrift des SEPA-Lastschriftmandats mit der Mandatsreferenz "{mandate[mandate]}", das zum Einzug deiner Mitgliedsbeiträge bei uns gespeichert ist.
-
-Sollten Angaben in diesem Mandat fehlerhaft oder veraltet sein, so teil uns dies bitte per E-Mail mit an vorstand@ccchb.de.
-
-
-Viele Grüße,
-Vorstand des Chaos Computer Club Bremen e.V.
-"""
-
-def create_email(mandate, pdfmandate):
-    msg = email.message.EmailMessage()
-    msg["To"] = f"{mandate['creditor_name']} <{mandate['email']}>"
-    msg["From"] = "Chaos Computer Club Bremen e.V. <vorstand@ccchb.de>"
-    msg["Subject"] = f"Dein SEPA-Lastschriftmandat (MREF: {mandate['mandate']})"
-    msg["Message-Id"] = email.utils.make_msgid(domain="verein.ccchb.de")
-    msg["Date"] = datetime.datetime.now()
-    msg.set_content(EMAIL_MESSAGE.format(mandate=mandate))
-    msg.add_attachment(pdfmandate, 'application', 'pdf', filename='Lastschriftmandat.pdf')
-    return msg
-
-def main_reify_mandate(mandate, output_dir_path, tex_template_path, tempdir_path, debug):
-    tex_jobname = str(tempdir_path.joinpath(mandate['mandate']))
-    settings_file_path = tempdir_path.joinpath(f'{mandate['mandate']}-settings.tex')
-    with open(settings_file_path, "w") as texfile:
-        texfile.write(create_tex(mandate))
-    latexmk_args = ["latexmk", "-lualatex", str(tex_template_path), f"-jobname={tex_jobname}"]
-    if not debug:
-        latexmk_args.append("-silent")
-    subprocess.run(latexmk_args)
-    pdf_file_path = tempdir_path.joinpath(f'{mandate['mandate']}.pdf')
-    pdf_output_path = output_dir_path.joinpath(f'{mandate['mandate']}.pdf')
-    shutil.copy(pdf_file_path, pdf_output_path)
-    if mandate['email']:
-        mail_output_path = output_dir_path.joinpath(f'{mandate['mandate']}.eml')
-        with open(pdf_file_path, "rb") as pdffile:
-            msg = create_email(mandate, pdffile.read())
-        with open(mail_output_path, "wb") as mailfile:
-            mailfile.write(bytes(msg))
-
-
-def main():
-    argparser = argparse.ArgumentParser()
-    argparser.add_argument("--csv-skip", default=1)
-    argparser.add_argument("--csv-fields", type=lambda s: s.split(","), default=DEFAULT_CSV_FIELDLIST)
-    argparser.add_argument("-O", "--output-dir", default="output/")
-    argparser.add_argument("--build-dir", default="build")
-    argparser.add_argument("--debug", default=False, action="store_true")
-    argparser.add_argument("tex_template")
-    argparser.add_argument("mandate_file")
-    args = argparser.parse_args()
-
-    output_dir_path = pathlib.Path(args.output_dir)
-    # Ensure that the output directory exists
-    output_dir_path.mkdir(parents=True, exist_ok=True)
-    tex_template_path = pathlib.Path(args.tex_template)
-    build_dir_path = pathlib.Path(args.build_dir)
-    # Ensure that the build directory exists
-    build_dir_path.mkdir(parents=True, exist_ok=True)
-
-    with open(args.mandate_file) as csvfile:
-        reader = csv.DictReader(csvfile, fieldnames=args.csv_fields)
-        for mandate in reader:
-            if not mandate.get('mandate'):
-                continue
-            main_reify_mandate(mandate, output_dir_path, tex_template_path, build_dir_path, args.debug)
-
-if __name__ == '__main__':
-    main()
diff --git a/triad/triad/client.py b/triad/triad/client.py
index 026b9ed..264b01e 100644
--- a/triad/triad/client.py
+++ b/triad/triad/client.py
@@ -71,6 +71,18 @@ class InvoicingClient(BaseClient):
         self.InvoiceLine = self.get_model('account.invoice.line', cls_name='InvoiceLine')
         self.PaymentTerm = self.get_model('account.invoice.payment_term', cls_name='PaymentTerm')
         self.PaymentTermLine = self.get_model('account.invoice.payment_term.line', cls_name='PaymentTermLine')
+    
+    def get_invoice_by_number(self, number):
+        try:
+            return self.Invoice.find([('number', '=', str(number))])[0]
+        except IndexError:
+            raise KeyError(number)
+    
+    def get_invoice_by_id(self, _id):
+        try:
+            return self.Invoice.find([('id', '=', str(_id))])[0]
+        except IndexError:
+            raise KeyError(_id)
 
 class PartyClient(BaseClient):
     def __init__(self, *args, **kwargs):
diff --git a/tryton-scripts/beitragsrechnungen.py b/tryton-scripts/beitragsrechnungen.py
index 045b464..a506353 100644
--- a/tryton-scripts/beitragsrechnungen.py
+++ b/tryton-scripts/beitragsrechnungen.py
@@ -17,8 +17,11 @@ argparser.add_argument('--reference-date', help='Referenzdatum für Zahlungsbedi
 argparser.add_argument('--claims-account', help='Forderungskonto', default='12001')
 argparser.add_argument('--fee-account', help='Beitragskonto', default='40000')
 argparser.add_argument('--default-payment-term', default='1m')
-argparser.add_argument('--csv-format', type=lambda x: x.split(",") if isinstance(x, str) else list(x), default='party_id,monthly_fee,payment_term,yearly_fee', help='CSV format specification')
+argparser.add_argument("-F", "--csv-fields", type=lambda f: f.split(","), help="csv fields")
 argparser.add_argument('-n', '--dry-run', action='store_true')
+argparser.add_argument("-o", "--output", help="output file", type=argparse.FileType("w"), default="-")
+argparser.add_argument("--update", help="update invoices", action="store_true")
+argparser.add_argument("--months", help="Beitragsmonate", type=lambda m: m.split(","), default="1,2,3,4,5,6,7,8,9,10,11,12")
 argparser.add_argument('year', help='Beitragsjahr', type=lambda s: datetime.date(int(s), 1, 1))
 argparser.add_argument('csvfile', nargs='?', type=argparse.FileType('r'), default='-')
 
@@ -40,7 +43,11 @@ def calculate_reference_date(date):
 if not args.reference_date:
     args.reference_date = calculate_reference_date(args.year)
 
-csvreader = csv.DictReader(args.csvfile, fieldnames=args.csv_format)
+args.months = [datetime.date(args.year.year, int(m), 1) for m in args.months]
+
+csvreader = csv.DictReader(args.csvfile, fieldnames=args.csv_fields)
+csvwriter = csv.DictWriter(args.output, fieldnames=csvreader.fieldnames + ["invoice_id"])
+csvwriter.writeheader()
 
 PAYMENT_TERMS_MAPPING = [
     ({'1m'}, 'Beitrag monatlich/jährlich'),
@@ -57,21 +64,28 @@ def load_payment_terms(session, invoicing_client):
     return ret
 
 
-def create_invoice(party, payment_term, monthly_fee, yearly_fee, claims_account, fee_account, invoicing_client, reference_date, year):
-    invoice = invoicing_client.Invoice()
+def create_invoice(party, payment_term, monthly_fee, months, yearly_fee, claims_account, fee_account, invoicing_client, reference_date, year, invoice_id, update):
+    if update:
+        invoice = invoicing_client.Invoice(int(invoice_id))
+    else:
+        invoice = invoicing_client.Invoice()
     invoice.type = 'out'
     invoice.party = party
     invoice.description = f"Beiträge {year.year}"
     invoice.account = claims_account
     invoice.payment_term = payment_term
     invoice.payment_term_date = reference_date
+    if update:
+        for line in invoice.lines:
+            invoice.lines.remove(line)
     if monthly_fee:
-        invoice_line = invoicing_client.InvoiceLine()
-        invoice_line.description = f"Monatsbeiträge Januar--Dezember {year.year}"
-        invoice_line.account = fee_account
-        invoice_line.quantity = decimal.Decimal(12) # Months
-        invoice_line.unit_price = decimal.Decimal(monthly_fee)
-        invoice.lines.append(invoice_line)
+        for month in months:
+            invoice_line = invoicing_client.InvoiceLine()
+            invoice_line.description = f"Beitrag {month.year}-{month.month}"
+            invoice_line.account = fee_account
+            invoice_line.quantity = decimal.Decimal(1)
+            invoice_line.unit_price = decimal.Decimal(monthly_fee)
+            invoice.lines.append(invoice_line)
     if yearly_fee:
         invoice_line = invoicing_client.InvoiceLine()
         invoice_line.description = f"Jahresbeitrag {year.year}"
@@ -118,11 +132,12 @@ with triad.client.Session.start(args.url, args.username, args.password) as sessi
             yearly_fee = None
         else:
             print(f'\tYearly fee: {yearly_fee}', file=sys.stderr)
-        invoice = create_invoice(party, payment_term, monthly_fee, yearly_fee, claims_account, fee_account, invoicing_client, args.reference_date, args.year)
+        invoice = create_invoice(party, payment_term, monthly_fee, args.months, yearly_fee, claims_account, fee_account, invoicing_client, args.reference_date, args.year, member.get('invoice_id'), args.update)
         if not args.dry_run:
             invoice.save()
         print(f'\tInvoice: {invoice.id}  {invoice.description}', file=sys.stderr)
         for line in invoice.lines:
-            print(f'\tLine: {line.description}  {line.quantity} * {line.unit_price}', file=sys.stderr)
+            print(f'\t\tLine: {line.description}    {line.unit_price}', file=sys.stderr)
         print(f'\tYearly fee: {invoice.total_amount}', file=sys.stderr)
-        print(f"{member['party_id']},{invoice.id},{invoice.total_amount},{payment_term.name}")
+        member['invoice_id'] = invoice.id
+        csvwriter.writerow(member)
diff --git a/tryton-scripts/mailings.py b/tryton-scripts/mailings.py
new file mode 100644
index 0000000..573cfbb
--- /dev/null
+++ b/tryton-scripts/mailings.py
@@ -0,0 +1,179 @@
+#!/bin/env python3
+
+import argparse
+import csv
+import datetime
+import decimal
+import email.message
+import getpass
+import pathlib
+import subprocess
+import tempfile
+
+import jinja2
+
+import triad.client
+
+class Env(object):
+    jinja2_env: jinja2.Environment
+    args: argparse.Namespace
+    session: triad.client.Session
+
+def fee_invoice(env: Env):
+    csvreader = csv.DictReader(env.args.csvfile, fieldnames=env.args.csv_fields)
+    csvwriter = csv.DictWriter(env.args.output, fieldnames=csvreader.fieldnames + ["message_id"])
+    csvwriter.writeheader()
+    invoicing_client = triad.client.InvoicingClient.from_session(env.session)
+    template = env.jinja2_env.get_template("beitrag.eml")
+    for member in csvreader:
+        invoice = invoicing_client.get_invoice_by_id(member['invoice_id'])
+        year = invoice.invoice_date or env.args.year
+        months = [datetime.date(year.year, month, 1) for month in range(1, 13)]
+        email_address = member.get('email') or invoice.party.email
+        try:
+            sepa_mandate = invoice.party.reception_direct_debits[0]
+        except IndexError:
+            sepa_mandate = None
+        else:
+            sepa_mandate = sepa_mandate.sepa_mandate
+        template_args = {
+            'monthly_fee': decimal.Decimal(member.get('monthly_fee') or '0.0'),
+            "yearly_fee": decimal.Decimal(member.get('yearly_fee') or '0.0'),
+            'invoice': invoice,
+            'sepa_mandate': sepa_mandate,
+            'payments': [],
+            'sender': env.args.email_sender,
+            "year": year,
+            "fee_months": [datetime.date(year.year, month, 1) for month in range(1, 13)]
+        }
+        msg = email.message.EmailMessage()
+        msg["From"] = env.args.email_from
+        msg["To"] = email_address
+        msg["Date"] = env.args.email_date or datetime.datetime.now()
+        msg["Subject"] = f"Beitragsrechnung {year.year} ({invoice.number})"
+        msg["Message-Id"] = email.utils.make_msgid(domain="verein.ccchb.de")
+        member['message_id'] = msg["Message-Id"]
+        msg.set_content(template.render(**template_args))
+        with (env.args.output_dir / member['message_id']).open("wb") as mailfile:
+            mailfile.write(bytes(msg))
+        csvwriter.writerow(member)
+
+def sepa_mandate(env: Env):
+    csvreader = csv.DictReader(env.args.csvfile, fieldnames=env.args.csv_fields)
+    csvwriter = csv.DictWriter(env.args.output, fieldnames=csvreader.fieldnames + ["message_id"])
+    csvwriter.writeheader()
+    client = triad.client.BaseClient.from_session(env.session)
+    template = env.jinja2_env.get_template("sepa_mandat.eml")
+    for mandate in csvreader:
+        email_address= mandate.get('email')
+        if 'sepa_mandate_ref' in mandate:
+            sepa_mandate = client.get_model('account.payment.sepa.mandate').find([('identification', '=', mandate['sepa_mandate_ref'])])
+            party = sepa_mandate.party
+        elif 'party_id' in mandate:
+            party = client.get_model('party.party').find([('code', '=', mandate['party_id'])])[0]
+            email_address = email_address or party.email
+            sepa_mandate = party.reception_direct_debits[0].sepa_mandate
+        else:
+            continue
+        template_args = {
+            "party": party,
+            "sepa_mandate": sepa_mandate
+        }
+        msg = email.message.EmailMessage()
+        msg["From"] = env.args.email_from
+        msg["To"] = email_address
+        msg["Date"] = env.args.email_date or datetime.datetime.now()
+        msg["Subject"] = f"SEPA-Lastschriftmandat MREF: {sepa_mandate.identification}"
+        msg["Message-Id"] = email.utils.make_msgid(domain="verein.ccchb.de")
+        mandate['message_id'] = msg["Message-Id"]
+        msg.set_content(template.render(**template_args))
+        if env.args.pdf:
+            msg.add_attachment(sepa_mandate_build_pdf(env, sepa_mandate), 'application', 'pdf', filename='SEPA-Lastschriftmandat.pdf')
+        with (env.args.output_dir / mandate['message_id']).open("wb") as mailfile:
+            mailfile.write(bytes(msg))
+        csvwriter.writerow(mandate)
+
+def sepa_mandate_build_pdf(env, sepa_mandate):
+    with tempfile.TemporaryDirectory() as tempdir:
+        tempdir_path = pathlib.Path(tempdir)
+        jobname = sepa_mandate.identification
+        with (tempdir_path / (jobname + "-settings.tex")).open("w") as fh:
+            fh.write(f'''
+\\csdef{{sepa-m001}}{{{sepa_mandate.identification}}}
+\\csdef{{sepa-m006}}{{Wiederkehrende Zahlung}}
+\\csdef{{sepa-p001}}{{{sepa_mandate.party.name}}}
+\\csdef{{sepa-d001}}{{{sepa_mandate.account_number.number}}}
+\\csdef{{sepa-m008}}{{{sepa_mandate.signature_date}}}
+\\csdef{{sepa-m009}}{{\\emph{{entfällt}}}}
+\\csdef{{sepa-d002a}}{{}}
+\\csdef{{sepa-d002b}}{{}}
+\\csdef{{sepa-p005}}{{}}
+\\csdef{{sepa-remarks}}{{Dieses Mandat ist eine Abschrift des dem Zahlungsempfänger vorliegenden, originalen SEPA-Lastschriftmandats.\\\\
+Erstellt am {datetime.date.today()}}}
+''')
+        compile_latex(jobname, env.args.latex_template, tempdir)
+        with (tempdir_path / (jobname + ".pdf")).open("rb") as fh:
+            return fh.read()
+
+def compile_latex(jobname, texfile, directory, debug=True):
+    latexmk_args = ["latexmk", "-lualatex", str(texfile), f"-jobname={jobname}"]
+    if not debug:
+        latexmk_args.append("-silent")
+    subprocess.run(latexmk_args, cwd=directory)
+
+def main():
+    parser = argparse.ArgumentParser()
+
+    parser.add_argument("-U", "--uri", help="Tryton URI")
+    parser.add_argument("-u", "--username", help="Tryton username")
+    parser.add_argument("-p", "--password", help="Tryton password")
+
+    parser.add_argument("-O", "--output-dir", help="email output directory", default=".", type=pathlib.Path)
+    parser.add_argument("-T", "--template-dir", help="email template directory", default="mail_templates")
+
+    # Email arguments
+    parser.add_argument('--email-sender', help='email signature sender')
+    parser.add_argument("--email-from", help="email from header")
+    parser.add_argument("--email-date", help="email date header")
+    
+    subparsers = parser.add_subparsers()
+
+    fee_invoice_parser = subparsers.add_parser("fee-invoice")
+    fee_invoice_parser.add_argument("-o", "--output", type=argparse.FileType("w"), default='-')
+    fee_invoice_parser.add_argument("-F", "--csv-fields", type=lambda f: f.split(","), help="csv fields")
+    fee_invoice_parser.add_argument("-y", "--year", type=lambda y: datetime.date(int(y), 1, 1))
+    fee_invoice_parser.add_argument("--months", help="Beitragsmonate", type=lambda m: m.split(","), default="1,2,3,4,5,6,7,8,9,10,11,12")
+    fee_invoice_parser.add_argument("csvfile", type=argparse.FileType("r"), default="-", nargs="?")
+    fee_invoice_parser.set_defaults(func=fee_invoice)
+
+    sepa_mandate_parser = subparsers.add_parser('sepa-mandate')
+    sepa_mandate_parser.add_argument('-o', '--output', type=argparse.FileType("w"), default='-')
+    sepa_mandate_parser.add_argument('-F', '--csv-fields', type=lambda f: f.split(','), help='csv fields')
+    sepa_mandate_parser.add_argument('--pdf', action='store_true', help='build pdf attachment', default=False)
+    sepa_mandate_parser.add_argument('--no-pdf', action='store_false', dest='pdf', help='don\'t build pdf attachment')
+    sepa_mandate_parser.add_argument('--latex-template', help='latex template in $TEXINPUTS')
+    sepa_mandate_parser.add_argument('csvfile', type=argparse.FileType('r'), default='-', nargs='?')
+    sepa_mandate_parser.set_defaults(func=sepa_mandate)
+
+    args = parser.parse_args()
+
+    env = Env()
+    env.jinja2_env = jinja2.Environment(
+        loader=jinja2.FileSystemLoader(args.template_dir)
+    )
+    env.args = args
+
+    if not args.uri:
+        args.uri = input("URI for Tryton: ")
+
+    if not args.username:
+        args.username = input("Username for Tryton: ")
+
+    if not args.password:
+        args.password = getpass.getpass(f"Password for Tryton user `{args.username}': ")
+
+    with triad.client.Session.start(args.uri, args.username, args.password) as session:
+        env.session = session
+        args.func(env)
+
+main()