path: root/docs/PAYROLL.md

# bokf — payroll (lön)

Status: Design draft · 2026-09-21 · License: GPL-3.0-or-later

Payroll for a small Swedish AB that runs monthly salaries from the books.
Wave 1 is the engine and the mandatory steps; the employee is the owner but
the schema and commands are multi-employee from the start. Wave 2 (the
lönebesked PDF and its delivery) and wave 3 (the TUI) are done.

## 1. Scope

**In (wave 1)**

- Employee register: name, personnummer (encrypted at rest), address,
  bank account, employment (monthly salary), salary account, tax table and
  column.
- Tax tables from Skatteverket: fetch, parse and store the official monthly
  tables, with a staleness check and a one-button refresh.
- One monthly payroll run per period: gross, tax, employer contributions,
  net, posting as a voucher.
- AGI underlag: the field values per employee and period for the manual
  declaration on skatteverket.se.
- Payment steps as buttons: pay salaries (the run voucher) and pay tax +
  contributions to the tax account (its own voucher), matched by the bank
  reconciliation.

**In (wave 2, done)**

- Employee e-mail (`employees.email`, schema v11) as the default lönebesked
  recipient.
- Lönebesked: one A4 PDF per employee and run, rendered with the invoice's
  visual language, stored as an attachment on the run's voucher and mailable
  with the existing SMTP path (`payroll.payslip`,
  `payroll.payslip_mail`). See §6.

**Out (later)**

- Semester/vacation accrual and vacation pay (skipped for now).
- AGI XML/filing, pension, benefits, foreign employees, växa-stöd,
  studiesocialt, löneväxling.

## 2. Accounts

Taken from the org's own imported history (2022–2026): 7210 for the owner's
salary, 7510 för arbetsgivaravgifter, 2710 personalskatt and 2731 avräkning.

| Item | Debit | Credit |
|---|---|---|
| Lönekörning | 7210 löner (per employee, default) | 2710 personalskatt, 1930 nettolön |
| Arbetsgivaravgifter | 7510 (31.42 %) | 2731 avräkning sociala avgifter |
| Betalning till skattekontot | 2710 + 2731 | 1630 skattekontot |

7010 is for kollektivanställda, 7210 för tjänstemän (what this org has used);
the account is a per-employee setting. Settings: `payroll_salary_account`
(default `7210`), `payroll_tax_account` (`2710`), `payroll_avgift_account`
(`7510`), `payroll_avgift_liability` (`2731`), `payroll_tax_payment_account`
(`1630`), `payroll_avgift_rate_bp` (default `3142`, basis points).

## 3. Schema v10 (v11 adds the employee e-mail)

```sql
CREATE TABLE employees (
  org_id           INTEGER NOT NULL REFERENCES orgs(id),
  id               INTEGER PRIMARY KEY,
  name             TEXT NOT NULL,
  personal_no_enc  TEXT NOT NULL,            -- enc:v1:... (AES-256-GCM)
  address          TEXT NOT NULL DEFAULT '',
  postal_code      TEXT NOT NULL DEFAULT '',
  city             TEXT NOT NULL DEFAULT '',
  bank_account     TEXT NOT NULL DEFAULT '',
  salary_account   TEXT NOT NULL DEFAULT '7210',
  monthly_salary_ore INTEGER NOT NULL DEFAULT 0 CHECK (monthly_salary_ore >= 0),
  tax_table        INTEGER NOT NULL DEFAULT 30 CHECK (tax_table BETWEEN 29 AND 42),
  tax_column       INTEGER NOT NULL DEFAULT 1 CHECK (tax_column BETWEEN 1 AND 6),
  active           INTEGER NOT NULL DEFAULT 1 CHECK (active IN (0,1)),
  created_at       TEXT NOT NULL,
  updated_at       TEXT,
  email            TEXT NOT NULL DEFAULT '',  -- v11, lönebesked recipient
  UNIQUE (org_id, id)
) STRICT;

CREATE TABLE payroll_runs (
  org_id          INTEGER NOT NULL REFERENCES orgs(id),
  id              INTEGER PRIMARY KEY,
  fiscal_year_id  INTEGER NOT NULL,
  period          TEXT NOT NULL,             -- YYYY-MM
  pay_date        TEXT NOT NULL,
  status          TEXT NOT NULL DEFAULT 'posted'
                    CHECK (status IN ('posted','paid')),
  gross_ore       INTEGER NOT NULL,
  tax_ore         INTEGER NOT NULL,
  avgifter_ore    INTEGER NOT NULL,
  net_ore         INTEGER NOT NULL,
  voucher_id      INTEGER,
  payment_voucher_id INTEGER,
  created_at      TEXT NOT NULL,
  created_by      INTEGER NOT NULL REFERENCES users(id),
  UNIQUE (org_id, id),
  UNIQUE (org_id, period, pay_date),
  FOREIGN KEY (org_id, fiscal_year_id) REFERENCES fiscal_years(org_id, id),
  FOREIGN KEY (org_id, voucher_id) REFERENCES vouchers(org_id, id),
  FOREIGN KEY (org_id, payment_voucher_id) REFERENCES vouchers(org_id, id)
) STRICT;

CREATE TABLE payroll_run_lines (
  org_id       INTEGER NOT NULL,
  id           INTEGER PRIMARY KEY,
  run_id       INTEGER NOT NULL,
  employee_id  INTEGER NOT NULL,
  gross_ore    INTEGER NOT NULL,
  tax_ore      INTEGER NOT NULL,
  avgifter_ore INTEGER NOT NULL,
  net_ore      INTEGER NOT NULL,
  tax_table    INTEGER NOT NULL,
  tax_column   INTEGER NOT NULL,
  UNIQUE (org_id, id),
  UNIQUE (org_id, run_id, employee_id),
  FOREIGN KEY (org_id, run_id) REFERENCES payroll_runs(org_id, id),
  FOREIGN KEY (org_id, employee_id) REFERENCES employees(org_id, id)
) STRICT;

-- National reference data, not tenant data: no org_id.
CREATE TABLE tax_tables (
  in_year       INTEGER NOT NULL,
  table_no      INTEGER NOT NULL,
  column_no     INTEGER NOT NULL,
  income_from_ore INTEGER NOT NULL,
  income_to_ore   INTEGER,                  -- NULL = open-ended top range
  tax_ore       INTEGER NOT NULL,           -- whole kronor for the range
  pct           INTEGER,                    -- top range percentage (x100)
  PRIMARY KEY (in_year, table_no, column_no, income_from_ore)
) STRICT;

CREATE TABLE tax_table_meta (
  in_year    INTEGER PRIMARY KEY,
  source_url TEXT NOT NULL,
  sha256     BLOB NOT NULL CHECK (length(sha256) = 32),
  fetched_at TEXT NOT NULL
) STRICT;
```

`vouchers.source` allows `'payroll'` and `'payroll_tax'` (widened CHECK in
v10; the same table rebuild as v9). v11 adds `employees.email` in a forward
migration (`ALTER TABLE`); `employee.create/update` accept it (at most 254
characters, no control characters) and `employee.list/get` return it.

## 4. Tax tables

Skatteverket publishes the complete monthly table as a fixed-width UTF-8
(BOM) TXT per income year, linked from "Teknisk beskrivning för
skattetabeller". 2026: `allmanna-tabeller-manad.txt`, ~389 kB, 7,965 lines.

Records (verified against the 2026 file):

```
30B29   2001   2100  150    0  150    0  150    2
30%29  80001  82200   30   30   26   27   35   35
```

- `30B<nn>`: monthly table `nn` (29–42), income range in whole kronor, then
  the tax for columns 1–6 in whole kronor.
- `30%<nn>`: the same tables above 80,000 kr/month; the columns are
  percentages (hundredths) that apply to the part of the income above the
  table's base, per SKV 433 (the technical description, fetched as PDF).
- The tax in the B records already includes grundavdrag, jobbskatteavdrag,
  public service fee and burial fee; use it as the withholding.

Commands:

- `payroll.tax_tables_fetch {year?}` (owner, audited): HTTPS GETs the
  technical page, finds that year's `allmanna-tabeller-manad.txt`, downloads
  and parses it, replaces the year's rows in one transaction and stores the
  source URL + SHA-256 in `tax_table_meta`. Missing year defaults to the
  current calendar year.
- `payroll.tax_tables_import {year, content_base64}` (owner, audited): the
  same parse from a supplied file (offline/air-gapped fallback).
- `payroll.tax_tables_status`: `{"stored_years":[...],"current_year":N,
  "stale":bool,"fetched_at":...,"source_url":...}`. The TUI shows a warning
  and the fetch button when `stale`.

The HTTPS GET uses OpenSSL directly (same stack as the SMTP client) with
system trust; the page URL is a constant, the file link is discovered by
matching `allmanna-tabeller-manad.txt` for the requested year.

## 5. Commands (wave 1)

| Command | Args | Result |
|---|---|---|
| `employee.list` | `active_only?` | items (personnummer masked) |
| `employee.get` | `id` | one employee (personnummer masked) |
| `employee.create` | `name`, `personal_no`, salary/account/table fields | created employee |
| `employee.update` | `id` + any field | effective employee |
| `employee.archive` | `id`, `active` | archived/reactivated |
| `payroll.tax_tables_fetch` | `year?` | `stored`, `rows`, `source_url`, `sha256` |
| `payroll.tax_tables_import` | `year`, `content_base64` | `stored`, `rows` |
| `payroll.tax_tables_status` | — | stored/current year, `stale` |
| `payroll.run_preview` | `period` (YYYY-MM) | per-employee gross/tax/avgifter/net and totals; nothing written |
| `payroll.run_post` | `period`, `pay_date`, `dry_run?` | run id, voucher id, totals |
| `payroll.run_list` | `limit?` | runs |
| `payroll.run_get` | `id` | run + lines |
| `payroll.agi` | `period` | per-employee AGI field values for the manual declaration |
| `payroll.pay_tax` | `run_id`, `date?`, `dry_run?` | payment voucher (D 2710 + D 2731, K 1630) |

`run_post` takes each active employee's `monthly_salary_ore` as gross (hourly
employees are out of scope in wave 1), withholds the table tax for their
table/column and books the two legs above in one transaction with
`source:"payroll"`. Taxation below 1,000 kr/year is not withheld (SKV rule)
and is handled at the run level. `pay_tax` books the payment with
`source:"payroll_tax"` and marks the run paid; the bank reconciliation
matches the bank leg to 1630 as usual.

The employer contribution rate is a setting (`payroll_avgift_rate_bp`,
default 3142) so växa-stöd/regional reductions can be handled manually later;
the base is the gross.

## 6. Documents and TUI

- **Lönebesked** (wave 2, done): `payroll.payslip` renders one A4 page per
  employee and run with the invoice's visual language — dark `#314c59`
  header bar, employer and employee blocks, gross, preliminary tax (shown
  negative), net and the employer-contribution note; the personnummer is
  masked except the last four. `payroll.payslip_mail` stores the PDF as an
  `application/pdf` attachment on the run's voucher, links it with
  `voucher_attachments` and e-mails it through the org's `smtp_*` settings
  to the employee's `email` (subject `Lönebesked <period>`, a short Swedish
  body with the net amount). A missing address is `INVALID_ARGS`, missing
  SMTP configuration `SMTP_NOT_CONFIGURED` and a failed delivery
  `SMTP_FAILED` (the stored attachment stays linked). `dry_run` validates,
  renders and stores nothing. See `PROTOCOL.md` §7.12.
- **TUI — Lön** (done, `clients/screens_payroll.c`): `Lönekörningar` (list,
  Ctrl+N for a new run) under Lön, `Anställda` under Företag, and a
  **Skattetabeller** screen (System, since the tables are national) with
  status, the Skatteverket fetch and the offline file import.
- The run screen shows the preview (F5), posts with Ctrl+Enter after
  confirmation, then offers the buttons **Lönebesked** (saves/opens the
  PDF), **AGI-underlag** (`payroll.agi` in a pager, owner only) and
  **Betala skatt & avgifter** (`payroll.pay_tax` with a date prompt) as
  manual steps. Steps that do not apply yet are dimmed with the reason.
  Posting and paying show the resulting voucher as `V-<n>`.
- The list title warns when the current year's tax tables are missing; a
  new run is refused with a pointer to Anställda when nobody has a monthly
  salary.

## 7. Testing

- Parser: fixture lines from the real 2026 file (B and % records), off-by-one
  ranges, BOM handling; tax lookup at range boundaries; the 80,000 kr/month
  boundary and the top-range percentage formula per SKV 433.
- Run posting: two employees, correct gross/tax/avgifter/net, balanced
  voucher with the configured accounts, `source:"payroll"`, AGI JSON values,
  pay_tax voucher and paid status; stale-table warning.
- Personnummer: encrypted at rest, masked in responses, decrypt for the AGI
  export only.