diff --git a/backend/Cargo.lock b/backend/Cargo.lock
index 9d6c881..7090c17 100644
--- a/backend/Cargo.lock
+++ b/backend/Cargo.lock
@@ -20,6 +20,12 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "arrayvec"
+version = "0.7.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8da52d66c7071e2e3fa2a1e5c6d088fec47b593032b254f5e980de8ea54454d6"
+
 [[package]]
 name = "async-trait"
 version = "0.1.58"
@@ -96,8 +102,10 @@ dependencies = [
  "chrono",
  "dotenvy",
  "hyper",
+ "iban_validate",
  "once_cell",
  "openssl",
+ "regex",
  "reqwest",
  "serde",
  "serde_json",
@@ -459,6 +467,16 @@ dependencies = [
  "cxx-build",
 ]
 
+[[package]]
+name = "iban_validate"
+version = "4.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cc1d358f7ae89819e8656f1b495c9d760a9ca315998b12d589dc516c9f81ed08"
+dependencies = [
+ "arrayvec",
+ "serde",
+]
+
 [[package]]
 name = "idna"
 version = "0.2.3"
@@ -873,9 +891,9 @@ dependencies = [
 
 [[package]]
 name = "regex"
-version = "1.7.0"
+version = "1.7.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e076559ef8e241f2ae3479e36f97bd5741c0330689e217ad51ce2c76808b868a"
+checksum = "48aaa5748ba571fb95cd2c85c09f629215d3a6ece942baa100950af03a34f733"
 dependencies = [
  "aho-corasick",
  "memchr",
diff --git a/backend/Cargo.toml b/backend/Cargo.toml
index a453bb1..bc93948 100644
--- a/backend/Cargo.toml
+++ b/backend/Cargo.toml
@@ -10,8 +10,10 @@ axum = { version = "0.6.0", features = ["multipart"] }
 chrono = { version = "0.4.23", features = ["serde"] }
 dotenvy = "0.15.6"
 hyper = { version = "0.14.23", features = ["full"] }
+iban_validate = { version = "4.0.1", features = ["serde"] }
 once_cell = "1.17.0"
 openssl = { version = "0.10.45", features = ["vendored"] }
+regex = "1.7.1"
 reqwest = { version = "0.11.13", features = ["json"] }
 serde = { version = "1.0.147", features = ["derive"] }
 serde_json = "1.0.91"
diff --git a/backend/src/main.rs b/backend/src/main.rs
index c757e92..a7089be 100644
--- a/backend/src/main.rs
+++ b/backend/src/main.rs
@@ -10,7 +10,8 @@ use axum::{
 use chrono::NaiveDate;
 use dotenvy::dotenv;
 use hyper::StatusCode;
-use serde::Deserialize;
+use iban::Iban;
+use serde::{Deserialize, Serialize};
 use std::net::SocketAddr;
 use tower_http::{limit::RequestBodyLimitLayer, trace::TraceLayer};
 use tracing_subscriber::{
@@ -57,7 +58,18 @@ async fn main() {
         .unwrap();
 }
 
-#[derive(Deserialize, Validate, Debug)]
+#[derive(Debug, Validate, Deserialize, Serialize)]
+#[serde(rename_all = "camelCase")]
+struct RequestInvoiceRow {
+    #[validate(range(min = 1))]
+    quantity: i32,
+    #[validate(range(min = 0))]
+    unit_price: f64,
+    #[validate(length(min = 1, max = 300))]
+    description: String,
+}
+
+#[derive(Debug, Validate, Deserialize)]
 #[serde(rename_all = "camelCase")]
 struct RequestBody {
     #[validate(length(min = 1, max = 300))]
@@ -66,7 +78,24 @@ struct RequestBody {
     last_name: String,
     #[validate(length(min = 1, max = 300))]
     street_address: String,
+    #[validate(length(min = 1, max = 10))]
+    zip: String,
+    #[validate(length(min = 1, max = 300))]
+    city: String,
+    #[validate(length(min = 1, max = 40))]
+    phone_number: String,
+    #[validate(length(min = 1, max = 600))]
+    email: String,
+    bank_account_number: Iban,
     invoice_date: NaiveDate,
+    #[validate(length(min = 1, max = 300))]
+    topic: String,
+    #[validate(length(min = 1, max = 5000))]
+    description: String,
+    #[validate(length(min = 1, max = 1000))]
+    other: String,
+    #[validate(length(min = 1))]
+    invoice_rows: Vec<RequestInvoiceRow>,
 }
 
 async fn handler(multipart: Multipart) -> Result<String, (StatusCode, String)> {
diff --git a/backend/src/procountor.rs b/backend/src/procountor.rs
index 5bee9eb..b2b049a 100644
--- a/backend/src/procountor.rs
+++ b/backend/src/procountor.rs
@@ -282,7 +282,7 @@ struct InvoiceRow {
     product: String,
     quantity: i32,
     unit: ProductUnit,
-    unit_price: f32,
+    unit_price: f64,
     discount_percent: i32,
     vat_percent: i32,
     vat_status: i32,