diff --git a/regimes/ca/README.md b/regimes/ca/README.md
new file mode 100644
index 00000000..3fd6bf1f
--- /dev/null
+++ b/regimes/ca/README.md
@@ -0,0 +1,3 @@
+# 🇨🇦 GOBL Canada Tax Regime
+
+Example Canada GOBL files can be found in the [`examples`](./examples) (YAML uncalculated documents) and [`examples/out`](./examples/out) (JSON calculated envelopes) subdirectories.
diff --git a/regimes/ca/ca.go b/regimes/ca/ca.go
new file mode 100644
index 00000000..b900600e
--- /dev/null
+++ b/regimes/ca/ca.go
@@ -0,0 +1,129 @@
+// Package ca provides models for dealing with Canada.
+package ca
+
+import (
+	"github.com/invopop/gobl/bill"
+	"github.com/invopop/gobl/cal"
+	"github.com/invopop/gobl/cbc"
+	"github.com/invopop/gobl/currency"
+	"github.com/invopop/gobl/i18n"
+	"github.com/invopop/gobl/l10n"
+	"github.com/invopop/gobl/num"
+	"github.com/invopop/gobl/tax"
+)
+
+func init() {
+	tax.RegisterRegime(New())
+}
+
+// Tax categories specific for Canada.
+const (
+	TaxCategoryHST cbc.Code = "HST"
+	TaxCategoryPST cbc.Code = "PST"
+)
+
+// New provides the tax region definition
+func New() *tax.Regime {
+	return &tax.Regime{
+		Country:  l10n.CA,
+		Currency: currency.CAD,
+		Name: i18n.String{
+			i18n.EN: "Canada",
+		},
+		TimeZone:  "America/Toronto", // Toronto
+		Validator: Validate,
+		Categories: []*tax.Category{
+			//
+			// General Sales Tax (GST)
+			//
+			{
+				Code: tax.CategoryGST,
+				Name: i18n.String{
+					i18n.EN: "GST",
+				},
+				Title: i18n.String{
+					i18n.EN: "General Sales Tax",
+				},
+				Sources: []*tax.Source{
+					{
+						Title: i18n.String{
+							i18n.EN: "GST/HST provincial rates table",
+						},
+						URL: "https://www.canada.ca/en/revenue-agency/services/tax/businesses/topics/gst-hst-businesses/charge-collect-which-rate/calculator.html",
+					},
+				},
+				Retained: false,
+				Rates: []*tax.Rate{
+					{
+						Key: tax.RateZero,
+						Name: i18n.String{
+							i18n.EN: "Zero Rate",
+						},
+						Description: i18n.String{
+							i18n.EN: "Some supplies are zero-rated under the GST, mainly: basic groceries, agricultural products, farm livestock, most fishery products such, prescription drugs and drug-dispensing services, certain medical devices, feminine hygiene products, exports, many transportation services where the origin or destination is outside Canada",
+						},
+						Values: []*tax.RateValue{
+							{
+								Percent: num.MakePercentage(0, 3),
+							},
+						},
+					},
+					{
+						Key: tax.RateStandard,
+						Name: i18n.String{
+							i18n.EN: "Standard rate",
+						},
+						Description: i18n.String{
+							i18n.EN: "For the majority of sales of goods and services: it applies to all products or services for which no other rate is expressly provided.",
+						},
+
+						Values: []*tax.RateValue{
+							{
+								Since:   cal.NewDate(2022, 1, 1),
+								Percent: num.MakePercentage(5, 2),
+							},
+						},
+					},
+				},
+			},
+			//
+			// Harmonized Sales Tax (HST)
+			//
+			{
+				Code: TaxCategoryHST,
+				Name: i18n.String{
+					i18n.EN: "HST",
+				},
+				Title: i18n.String{
+					i18n.EN: "Harmonized Sales Tax",
+				},
+				// TODO: determine local rates
+				Rates: []*tax.Rate{},
+			},
+
+			//
+			// Provincial Sales Tax (PST)
+			//
+			{
+				Code: TaxCategoryPST,
+				Name: i18n.String{
+					i18n.EN: "PST",
+				},
+				Title: i18n.String{
+					i18n.EN: "Provincial Sales Tax",
+				},
+				// TODO: determine local rates
+				Rates: []*tax.Rate{},
+			},
+		},
+	}
+}
+
+// Validate checks the document type and determines if it can be validated.
+func Validate(doc interface{}) error {
+	switch obj := doc.(type) {
+	case *bill.Invoice:
+		return validateInvoice(obj)
+	}
+	return nil
+}
diff --git a/regimes/ca/examples/invoice-ca-ca.yaml b/regimes/ca/examples/invoice-ca-ca.yaml
new file mode 100644
index 00000000..b062700f
--- /dev/null
+++ b/regimes/ca/examples/invoice-ca-ca.yaml
@@ -0,0 +1,37 @@
+$schema: "https://gobl.org/draft-0/bill/invoice"
+currency: "CAD"
+issue_date: "2023-04-21"
+series: "SAMPLE"
+code: "001"
+
+supplier:
+  tax_id:
+    country: "CA"
+  name: "Provide One Inc."
+  emails:
+    - addr: "billing@provideone.com"
+  addresses:
+    - num: "151"
+      street: "O'Connor Street"
+      locality: "Ottawa"
+      region: "ON"
+      code: "K2P 2L8"
+      country: "CA"
+
+customer:
+  name: "Sample Consumer"
+  emails:
+    - addr: "email@sample.com"
+
+lines:
+  - quantity: 20
+    item:
+      name: "Development services"
+      price: "90.00"
+      unit: "h"
+    discounts:
+      - percent: "10%"
+        reason: "Special discount"
+    taxes:
+      - cat: GST
+        percent: "8.5%"
diff --git a/regimes/ca/examples/out/invoice-ca-ca.json b/regimes/ca/examples/out/invoice-ca-ca.json
new file mode 100644
index 00000000..470ab043
--- /dev/null
+++ b/regimes/ca/examples/out/invoice-ca-ca.json
@@ -0,0 +1,97 @@
+{
+	"$schema": "https://gobl.org/draft-0/envelope",
+	"head": {
+		"uuid": "8a51fd30-2a27-11ee-be56-0242ac120002",
+		"dig": {
+			"alg": "sha256",
+			"val": "3d1cd0dd9fb113e244bddbdb7cefdb8be5c1a9ab3d60928cc225303cc1a2326b"
+		},
+		"draft": true
+	},
+	"doc": {
+		"$schema": "https://gobl.org/draft-0/bill/invoice",
+		"type": "standard",
+		"series": "SAMPLE",
+		"code": "001",
+		"issue_date": "2023-04-21",
+		"currency": "CAD",
+		"supplier": {
+			"name": "Provide One Inc.",
+			"tax_id": {
+				"country": "CA"
+			},
+			"addresses": [
+				{
+					"num": "151",
+					"street": "O'Connor Street",
+					"locality": "Ottawa",
+					"region": "ON",
+					"code": "K2P 2L8",
+					"country": "CA"
+				}
+			],
+			"emails": [
+				{
+					"addr": "billing@provideone.com"
+				}
+			]
+		},
+		"customer": {
+			"name": "Sample Consumer",
+			"emails": [
+				{
+					"addr": "email@sample.com"
+				}
+			]
+		},
+		"lines": [
+			{
+				"i": 1,
+				"quantity": "20",
+				"item": {
+					"name": "Development services",
+					"price": "90.00",
+					"unit": "h"
+				},
+				"sum": "1800.00",
+				"discounts": [
+					{
+						"percent": "10%",
+						"amount": "180.00",
+						"reason": "Special discount"
+					}
+				],
+				"taxes": [
+					{
+						"cat": "GST",
+						"percent": "8.5%"
+					}
+				],
+				"total": "1620.00"
+			}
+		],
+		"totals": {
+			"sum": "1620.00",
+			"total": "1620.00",
+			"taxes": {
+				"categories": [
+					{
+						"code": "GST",
+						"rates": [
+							{
+								"base": "1620.00",
+								"percent": "8.5%",
+								"amount": "137.70"
+							}
+						],
+						"amount": "137.70"
+					}
+				],
+				"sum": "137.70"
+			},
+			"tax": "137.70",
+			"total_with_tax": "1757.70",
+			"payable": "1757.70"
+		}
+	}
+}
\ No newline at end of file
diff --git a/regimes/ca/invoice_validator.go b/regimes/ca/invoice_validator.go
new file mode 100644
index 00000000..35e789bf
--- /dev/null
+++ b/regimes/ca/invoice_validator.go
@@ -0,0 +1,27 @@
+package ca
+
+import (
+	"github.com/invopop/gobl/bill"
+	"github.com/invopop/gobl/currency"
+	"github.com/invopop/validation"
+)
+
+// invoiceValidator adds validation checks to invoices which are relevant
+// for the region.
+type invoiceValidator struct {
+	inv *bill.Invoice
+}
+
+func validateInvoice(inv *bill.Invoice) error {
+	v := &invoiceValidator{inv: inv}
+	return v.validate()
+}
+
+func (v *invoiceValidator) validate() error {
+	inv := v.inv
+	return validation.ValidateStruct(inv,
+		validation.Field(&inv.Currency, validation.In(currency.CAD)),
+		validation.Field(&inv.Supplier, validation.Required),
+		validation.Field(&inv.Customer),
+	)
+}
diff --git a/regimes/common/invoice_tags.go b/regimes/common/invoice_tags.go
index 8748ba86..2a41f023 100644
--- a/regimes/common/invoice_tags.go
+++ b/regimes/common/invoice_tags.go
@@ -14,11 +14,13 @@ var invoiceTags = []*tax.KeyDefinition{
 			i18n.EN: "Simplified Invoice",
 			i18n.ES: "Factura Simplificada",
 			i18n.IT: "Fattura Semplificata",
+			i18n.DE: "Vereinfachte Rechnung",
 		},
 		Desc: i18n.String{
 			i18n.EN: "Used for B2C transactions when the client details are not available, check with local authorities for limits.",
 			i18n.ES: "Usado para transacciones B2C cuando los detalles del cliente no están disponibles, consulte con las autoridades locales para los límites.",
 			i18n.IT: "Utilizzato per le transazioni B2C quando i dettagli del cliente non sono disponibili, controllare con le autorità locali per i limiti.",
+			i18n.DE: "Wird für B2C-Transaktionen verwendet, wenn die Kundendaten nicht verfügbar sind. Bitte wenden Sie sich an die örtlichen Behörden, um die Grenzwerte zu ermitteln.",
 		},
 	},
 
@@ -31,6 +33,7 @@ var invoiceTags = []*tax.KeyDefinition{
 			i18n.EN: "Reverse Charge",
 			i18n.ES: "Inversión del Sujeto Pasivo",
 			i18n.IT: "Inversione del soggetto passivo",
+			i18n.DE: "Umkehr der Steuerschuld",
 		},
 	},
 
@@ -43,6 +46,7 @@ var invoiceTags = []*tax.KeyDefinition{
 			i18n.EN: "Self-billed",
 			i18n.ES: "Facturación por el destinatario",
 			i18n.IT: "Autofattura",
+			i18n.DE: "Rechnung durch den Leistungsempfänger",
 		},
 	},
 
@@ -52,6 +56,8 @@ var invoiceTags = []*tax.KeyDefinition{
 		Name: i18n.String{
 			i18n.EN: "Customer rates",
 			i18n.ES: "Tarifas aplicables al destinatario",
+			i18n.IT: "Aliquote applicabili al destinatario",
+			i18n.DE: "Kundensätze",
 		},
 	},
 }
diff --git a/regimes/de/README.md b/regimes/de/README.md
new file mode 100644
index 00000000..ceb844b6
--- /dev/null
+++ b/regimes/de/README.md
@@ -0,0 +1,3 @@
+# 🇩🇪 GOBL Germany Tax Regime
+
+Example DE GOBL files can be found in the [`examples`](./examples) (YAML uncalculated documents) and [`examples/out`](./examples/out) (JSON calculated envelopes) subdirectories.
diff --git a/regimes/de/de.go b/regimes/de/de.go
new file mode 100644
index 00000000..155beb15
--- /dev/null
+++ b/regimes/de/de.go
@@ -0,0 +1,62 @@
+// Package de provides the tax region definition for Germany.
+package de
+
+import (
+	"github.com/invopop/gobl/bill"
+	"github.com/invopop/gobl/cbc"
+	"github.com/invopop/gobl/i18n"
+	"github.com/invopop/gobl/l10n"
+	"github.com/invopop/gobl/regimes/common"
+	"github.com/invopop/gobl/tax"
+)
+
+func init() {
+	tax.RegisterRegime(New())
+}
+
+// New provides the tax region definition
+func New() *tax.Regime {
+	return &tax.Regime{
+		Country:  l10n.DE,
+		Currency: "EUR",
+		Name: i18n.String{
+			i18n.EN: "Germany",
+			i18n.FR: "Deutschland",
+		},
+		TimeZone: "Europe/Berlin",
+		Tags:     common.InvoiceTags(),
+		Scenarios: []*tax.ScenarioSet{
+			invoiceScenarios,
+		},
+		Corrections: []*tax.CorrectionDefinition{
+			{
+				Schema: bill.ShortSchemaInvoice,
+				// Germany only supports credit notes to correct an invoice
+				Types: []cbc.Key{
+					bill.InvoiceTypeCreditNote,
+				},
+			},
+		},
+		Validator:  Validate,
+		Calculator: Calculate,
+		Categories: taxCategories,
+	}
+}
+
+// Validate checks the document type and determines if it can be validated.
+func Validate(doc interface{}) error {
+	switch obj := doc.(type) {
+	case *tax.Identity:
+		return validateTaxIdentity(obj)
+	}
+	return nil
+}
+
+// Calculate will attempt to clean the object passed to it.
+func Calculate(doc interface{}) error {
+	switch obj := doc.(type) {
+	case *tax.Identity:
+		return common.NormalizeTaxIdentity(obj)
+	}
+	return nil
+}
diff --git a/regimes/de/examples/invoice-de-de.yaml b/regimes/de/examples/invoice-de-de.yaml
new file mode 100644
index 00000000..f6ca698b
--- /dev/null
+++ b/regimes/de/examples/invoice-de-de.yaml
@@ -0,0 +1,46 @@
+$schema: "https://gobl.org/draft-0/bill/invoice"
+currency: "EUR"
+issue_date: "2022-02-01"
+series: "SAMPLE"
+code: "001"
+
+supplier:
+  tax_id:
+    country: "DE"
+    code: "111111125" # random
+  name: "Provide One GmbH"
+  emails:
+    - addr: "billing@example.com"
+  addresses:
+    - num: "16"
+      street: "Dietmar-Hopp-Allee"
+      locality: "Walldorf"
+      code: "69190"
+      country: "DE"
+
+customer:
+  tax_id:
+    country: "DE"
+    code: "282741168"
+  name: "Sample Consumer"
+  emails:
+    - addr: "email@sample.com"
+  addresses:
+    - num: "25"
+      street: "Werner-Heisenberg-Allee"
+      locality: "München"
+      code: "80939"
+      country": "DE"
+
+lines:
+  - quantity: 20
+    item:
+      name: "Development services"
+      price: "90.00"
+      unit: "h"
+    discounts:
+      - percent: "10%"
+        reason: "Special discount"
+    taxes:
+      - cat: VAT
+        rate: standard
diff --git a/regimes/de/examples/out/invoice-de-de.json b/regimes/de/examples/out/invoice-de-de.json
new file mode 100644
index 00000000..99d3859e
--- /dev/null
+++ b/regimes/de/examples/out/invoice-de-de.json
@@ -0,0 +1,111 @@
+{
+	"$schema": "https://gobl.org/draft-0/envelope",
+	"head": {
+		"uuid": "8a51fd30-2a27-11ee-be56-0242ac120002",
+		"dig": {
+			"alg": "sha256",
+			"val": "fb3e81ee5d0964fa423dcfb62309a7a5c5150dc62cdd81427a68a2c85e893a66"
+		},
+		"draft": true
+	},
+	"doc": {
+		"$schema": "https://gobl.org/draft-0/bill/invoice",
+		"type": "standard",
+		"series": "SAMPLE",
+		"code": "001",
+		"issue_date": "2022-02-01",
+		"currency": "EUR",
+		"supplier": {
+			"name": "Provide One GmbH",
+			"tax_id": {
+				"country": "DE",
+				"code": "111111125"
+			},
+			"addresses": [
+				{
+					"num": "16",
+					"street": "Dietmar-Hopp-Allee",
+					"locality": "Walldorf",
+					"code": "69190",
+					"country": "DE"
+				}
+			],
+			"emails": [
+				{
+					"addr": "billing@example.com"
+				}
+			]
+		},
+		"customer": {
+			"name": "Sample Consumer",
+			"tax_id": {
+				"country": "DE",
+				"code": "282741168"
+			},
+			"addresses": [
+				{
+					"num": "25",
+					"street": "Werner-Heisenberg-Allee",
+					"locality": "München",
+					"code": "80939"
+				}
+			],
+			"emails": [
+				{
+					"addr": "email@sample.com"
+				}
+			]
+		},
+		"lines": [
+			{
+				"i": 1,
+				"quantity": "20",
+				"item": {
+					"name": "Development services",
+					"price": "90.00",
+					"unit": "h"
+				},
+				"sum": "1800.00",
+				"discounts": [
+					{
+						"percent": "10%",
+						"amount": "180.00",
+						"reason": "Special discount"
+					}
+				],
+				"taxes": [
+					{
+						"cat": "VAT",
+						"rate": "standard",
+						"percent": "19%"
+					}
+				],
+				"total": "1620.00"
+			}
+		],
+		"totals": {
+			"sum": "1620.00",
+			"total": "1620.00",
+			"taxes": {
+				"categories": [
+					{
+						"code": "VAT",
+						"rates": [
+							{
+								"key": "standard",
+								"base": "1620.00",
+								"percent": "19%",
+								"amount": "307.80"
+							}
+						],
+						"amount": "307.80"
+					}
+				],
+				"sum": "307.80"
+			},
+			"tax": "307.80",
+			"total_with_tax": "1927.80",
+			"payable": "1927.80"
+		}
+	}
+}
\ No newline at end of file
diff --git a/regimes/de/scenarios.go b/regimes/de/scenarios.go
new file mode 100644
index 00000000..1c09757b
--- /dev/null
+++ b/regimes/de/scenarios.go
@@ -0,0 +1,23 @@
+package de
+
+import (
+	"github.com/invopop/gobl/bill"
+	"github.com/invopop/gobl/cbc"
+	"github.com/invopop/gobl/tax"
+)
+
+var invoiceScenarios = &tax.ScenarioSet{
+	Schema: bill.ShortSchemaInvoice,
+	List: []*tax.Scenario{
+		// ** Special Messages **
+		// Reverse Charges
+		{
+			Tags: []cbc.Key{tax.TagReverseCharge},
+			Note: &cbc.Note{
+				Key:  cbc.NoteKeyLegal,
+				Src:  tax.TagReverseCharge,
+				Text: "Reverse Charge / Umkehr der Steuerschuld.",
+			},
+		},
+	},
+}
diff --git a/regimes/de/tax_categories.go b/regimes/de/tax_categories.go
new file mode 100644
index 00000000..fdb81848
--- /dev/null
+++ b/regimes/de/tax_categories.go
@@ -0,0 +1,108 @@
+package de
+
+import (
+	"github.com/invopop/gobl/cal"
+	"github.com/invopop/gobl/i18n"
+	"github.com/invopop/gobl/num"
+	"github.com/invopop/gobl/tax"
+)
+
+var taxCategories = []*tax.Category{
+	//
+	// VAT
+	//
+	{
+		Code: tax.CategoryVAT,
+		Name: i18n.String{
+			i18n.EN: "VAT",
+			i18n.DE: "MwSt",
+		},
+		Title: i18n.String{
+			i18n.EN: "Value Added Tax",
+			i18n.DE: "Mehrwertsteuer",
+		},
+		Sources: []*tax.Source{
+			{
+				Title: i18n.String{
+					i18n.EN: "Value Added Tax/Goods and Services Tax (VAT/GST) (1976-2023)",
+					i18n.DE: "Umsatzsteuer/Güter - und Dienstleistungssteuer (USt/GST) (1976-2023)",
+				},
+				URL: "https://www.oecd.org/tax/tax-policy/tax-database/",
+			},
+		},
+		Retained: false,
+		Rates: []*tax.Rate{
+			{
+				Key: tax.RateZero,
+				Name: i18n.String{
+					i18n.EN: "Zero Rate",
+					i18n.DE: "Nullsatz",
+				},
+				Values: []*tax.RateValue{
+					{
+						Percent: num.MakePercentage(0, 3),
+					},
+				},
+			},
+			{
+				Key: tax.RateStandard,
+				Name: i18n.String{
+					i18n.EN: "Standard rate",
+					i18n.DE: "Standardsteuersatz",
+				},
+				Description: i18n.String{
+					i18n.EN: "For the majority of sales of goods and services: it applies to all products or services for which no other rate is expressly provided.",
+					i18n.DE: "Für den Großteil der Verkäufe von Waren und Dienstleistungen gilt: Dies gilt für alle Produkte oder Dienstleistungen, für die ausdrücklich kein anderer Satz festgelegt ist.",
+				},
+
+				Values: []*tax.RateValue{
+					{
+						Since:   cal.NewDate(2022, 1, 1),
+						Percent: num.MakePercentage(19, 2),
+					},
+					{
+						Since:   cal.NewDate(2020, 7, 1), // COVID temporary measures
+						Percent: num.MakePercentage(16, 2),
+					},
+					{
+						Since:   cal.NewDate(2007, 7, 1),
+						Percent: num.MakePercentage(19, 2),
+					},
+					{
+						Since:   cal.NewDate(1993, 1, 1),
+						Percent: num.MakePercentage(16, 2),
+					},
+				},
+			},
+			{
+				Key: tax.RateReduced,
+				Name: i18n.String{
+					i18n.EN: "Reduced rate",
+					i18n.DE: "Verminderter Steuersatz",
+				},
+				Description: i18n.String{
+					i18n.EN: "Applicable in particular to basic foodstuffs, books and magazines, cultural events, hotel accommodations, public transportation, medical products, or home renovation.",
+					i18n.DE: "Insbesondere anwendbar auf Grundnahrungsmittel, Bücher und Zeitschriften, kulturelle Veranstaltungen, Hotelunterkünfte, öffentliche Verkehrsmittel, medizinische Produkte oder Hausrenovierung.",
+				},
+				Values: []*tax.RateValue{
+					{
+						Since:   cal.NewDate(2022, 1, 1),
+						Percent: num.MakePercentage(7, 2),
+					},
+					{
+						Since:   cal.NewDate(2020, 7, 1), // COVID temporary measures
+						Percent: num.MakePercentage(5, 2),
+					},
+					{
+						Since:   cal.NewDate(2007, 7, 1),
+						Percent: num.MakePercentage(7, 2),
+					},
+					{
+						Since:   cal.NewDate(1993, 1, 1),
+						Percent: num.MakePercentage(5, 2),
+					},
+				},
+			},
+		},
+	},
+}
diff --git a/regimes/de/tax_identity.go b/regimes/de/tax_identity.go
new file mode 100644
index 00000000..713881a4
--- /dev/null
+++ b/regimes/de/tax_identity.go
@@ -0,0 +1,80 @@
+package de
+
+import (
+	"errors"
+	"regexp"
+	"strconv"
+
+	"github.com/invopop/gobl/cbc"
+	"github.com/invopop/gobl/tax"
+	"github.com/invopop/validation"
+)
+
+// Reference: https://github.com/ltns35/go-vat/blob/main/countries/germany.go
+
+var (
+	taxCodeRegexps = []*regexp.Regexp{
+		regexp.MustCompile(`^[1-9]\d{8}$`),
+	}
+)
+
+// validateTaxIdentity checks to ensure the NIT code looks okay.
+func validateTaxIdentity(tID *tax.Identity) error {
+	return validation.ValidateStruct(tID,
+		validation.Field(&tID.Code, validation.By(validateTaxCode)),
+	)
+}
+
+func validateTaxCode(value interface{}) error {
+	code, ok := value.(cbc.Code)
+	if !ok || code == "" {
+		return nil
+	}
+	val := code.String()
+
+	match := false
+	for _, re := range taxCodeRegexps {
+		if re.MatchString(val) {
+			match = true
+			break
+		}
+	}
+	if !match {
+		return errors.New("invalid format")
+	}
+
+	return validateTaxCodeChecksum(val)
+}
+
+func validateTaxCodeChecksum(val string) error {
+	p := 10
+	sum := 0
+	cd := 0
+	for i := 0; i < 8; i++ {
+		digit, err := strconv.Atoi(string(val[i]))
+		if err != nil {
+			return errors.New("invalid digit")
+		}
+		sum = (digit + p) % 10
+		if sum == 0 {
+			sum = 10
+		}
+		p = (2 * sum) % 11
+	}
+
+	if 11-p == 10 {
+		cd = 0
+	} else {
+		cd = 11 - p
+	}
+
+	ecd, err := strconv.Atoi(string(val[8]))
+	if err != nil {
+		return errors.New("invalid checksum")
+	}
+	if cd != ecd {
+		return errors.New("checksum mismatch")
+	}
+
+	return nil
+}
diff --git a/regimes/de/tax_identity_test.go b/regimes/de/tax_identity_test.go
new file mode 100644
index 00000000..32edcbd1
--- /dev/null
+++ b/regimes/de/tax_identity_test.go
@@ -0,0 +1,73 @@
+package de_test
+
+import (
+	"testing"
+
+	"github.com/invopop/gobl/cbc"
+	"github.com/invopop/gobl/l10n"
+	"github.com/invopop/gobl/regimes/de"
+	"github.com/invopop/gobl/tax"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestValidateTaxIdentity(t *testing.T) {
+	tests := []struct {
+		name string
+		code cbc.Code
+		err  string
+	}{
+		{name: "good 1", code: "111111125"},
+		{name: "good 2", code: "160459932"},
+		{name: "good 3", code: "282741168"},
+		{name: "good 4", code: "813495425"},
+		{
+			name: "zeros",
+			code: "000000000",
+			err:  "invalid format",
+		},
+		{
+			name: "start with zero",
+			code: "011111112",
+			err:  "invalid format",
+		},
+		{
+			name: "bad mid length",
+			code: "12345678910",
+			err:  "invalid format",
+		},
+		{
+			name: "too long",
+			code: "1234567890123",
+			err:  "invalid format",
+		},
+		{
+			name: "too short",
+			code: "123456",
+			err:  "invalid format",
+		},
+		{
+			name: "not normalized",
+			code: "12.449.965-4",
+			err:  "invalid format",
+		},
+		{
+			name: "bad checksum",
+			code: "999999991",
+			err:  "checksum mismatch",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			tID := &tax.Identity{Country: l10n.DE, Code: tt.code}
+			err := de.Validate(tID)
+			if tt.err == "" {
+				assert.NoError(t, err)
+			} else {
+				if assert.Error(t, err) {
+					assert.Contains(t, err.Error(), tt.err)
+				}
+			}
+		})
+	}
+}
diff --git a/regimes/regimes.go b/regimes/regimes.go
index b4ccad33..60371b45 100644
--- a/regimes/regimes.go
+++ b/regimes/regimes.go
@@ -5,7 +5,9 @@ package regimes
 import (
 	// Import all the regime definitions which will automatically
 	// add themselves to the tax regime register.
+	_ "github.com/invopop/gobl/regimes/ca"
 	_ "github.com/invopop/gobl/regimes/co"
+	_ "github.com/invopop/gobl/regimes/de"
 	_ "github.com/invopop/gobl/regimes/es"
 	_ "github.com/invopop/gobl/regimes/fr"
 	_ "github.com/invopop/gobl/regimes/gb"