We can use /rest/V1/customers/rest/V1/customers: http://devdocs.magento.com/swagger/#!/customerAccountManagementV1http://devdocs.magento.com/swagger/#resource_customerAccountManagementV1
For example, payload:
{
"id": 0,
"group_id": 0,
"default_billing": "string",
"default_shipping": "string",
"confirmation": "string",
"created_at": "string",
"updated_at": "string",
"created_in": "string",
"dob": "string",
"email": "string",
"firstname": "string",
"lastname": "string",
"middlename": "string",
"prefix": "string",
"suffix": "string",
"gender": 0,
"store_id": 0,
"taxvat": "string",
"website_id": 0,
"addresses": [
{
"id": 0,
"customer_id": 0,
"region": {
"region_code": "string",
"region": "string",
"region_id": 0,
"extension_attributes": {}
},
"region_id": 0,
"country_id": "string",
"street": [
"string"
],
"company": "string",
"telephone": "string",
"fax": "string",
"postcode": "string",
"city": "string",
"firstname": "string",
"lastname": "string",
"middlename": "string",
"prefix": "string",
"suffix": "string",
"vat_id": "string",
"default_shipping": true,
"default_billing": true,
"extension_attributes": {},
"custom_attributes": [
{
"attribute_code": "string",
"value": "string"
}
]
}
],