PostFinance Exchange Rate API: CHF Buy and Sell Rates as JSON

PostFinance is the financial services arm of Swiss Post. Its currency converter shows account (Giro), fast-payment and cash rates against the franc; the two-way account rates cover about 18 currencies. This guide shows how to read that board as JSON: what the rates mean, how they compare with the Swiss National Bank official rate and with other banks in Switzerland, and the calls that return them.

What the PostFinance board shows

• 18 currencies against the Swiss franc: AUD, CAD, CZK, DKK, EUR, GBP, HKD, HUF, JPY, MAD, NOK, NZD, PLN, SEK, SGD, THB, USD and ZAR. Every value is CHF per 1 unit of the foreign currency.
• The giro (account) exchange rates, up to CHF 50'000 pair. Swiss banks publish two lists for each currency: Devisen, the non-cash rate for transfers, account conversions and card payments, and Noten, the cash rate for bank notes, whose spread is several times wider. Many quote SEK, NOK, DKK, JPY and other currencies per 100 units, with tiers by amount; the rates here are the Devisen pair at the smallest tier, converted to francs per 1 unit. The Swiss National Bank official rate is shown next to each row.
• USD on 15 November 2026: PostFinance bought at 0.825 and sold at 0.8458 CHF, a spread of 2.49%. The Swiss National Bank official rate was 0.837, so the bank's mid sat -0.19% from it.
• The bank's own timestamp. The page prints a last-updated stamp (2026-11-15 12:00:00 on the board above), returned as bank_updated_at next to our captured_at.
• Every day's board is kept permanently, from 13 November 2026. Read one past day with ?date=, or a range for one currency with the /history endpoint (paid plans).

Spreads across the board

On the 15 November 2026 board the tightest spreads were SEK (2.40%), EUR (2.40%), DKK (2.42%) and the widest MAD (6.00%), ZAR (4.02%), THB (3.50%). Spread is (sell − buy) ÷ mid: what a round trip through the bank costs, before any fees. The API returns it on every row as spread_pct, so you can rank currencies or alert when a bank widens its board.

USD at PostFinance and other banks in Switzerland

USD on the 21 boards AllRatesToday reads in Switzerland, all captured on 15 November 2026 (the Swiss National Bank official rate was 0.837):

PostFinance had the 3rd narrowest USD spread of the 21. One call to /api/v1/bank-rates/ch returns every board in the table at once.

Get the board (REST)

You need an API key; the free key works. The full board:

curl "https://allratestoday.com/api/v1/bank-rates/ch/postfinance" \
  -H "Authorization: Bearer art_live_your_key"

What comes back (the 15 November 2026 board, first three rows):

{
  "bank": "postfinance",
  "name": "PostFinance",
  "country": "ch",
  "quote_ccy": "CHF",
  "bank_updated_at": "2026-11-15 12:00:00",
  "basis": "Giro (account) exchange rates, up to CHF 50'000",
  "captured_at": "2026-11-15T11:52:27.765Z",
  "rates": [
    {"ccy":"AUD","buy":0.5594,"sell":0.5764,"mid":0.5679,"spread_pct":2.993,"official":0.57902,"vs_official_pct":-1.92},
    {"ccy":"CAD","buy":0.5786,"sell":0.5932,"mid":0.5859,"spread_pct":2.492,"official":0.58594,"vs_official_pct":-0.007},
    {"ccy":"CZK","buy":0.03734,"sell":0.038478,"mid":0.037909,"spread_pct":3.002,"official":0.0381034,"vs_official_pct":-0.51},
    … 15 more currencies
  ],
  "disclaimer": "…",
  "attribution": { … }
}

One currency, with the row fields at the top level:

curl "https://allratestoday.com/api/v1/bank-rates/ch/postfinance?ccy=USD" \
  -H "Authorization: Bearer art_live_your_key"

{
  "bank": "postfinance",
  "name": "PostFinance",
  "country": "ch",
  "quote_ccy": "CHF",
  "bank_updated_at": "2026-11-15 12:00:00",
  "basis": "Giro (account) exchange rates, up to CHF 50'000",
  "captured_at": "2026-11-15T11:52:27.765Z",
  "ccy": "USD",
  "buy": 0.825,
  "sell": 0.8458,
  "mid": 0.8354,
  "spread_pct": 2.49,
  "official": 0.837,
  "vs_official_pct": -0.191,
  "disclaimer": "Retail buy/sell rates as displayed on each bank’s own website at capture time, quoted as home currency per 1 unit of foreign currency. Indicative only: banks change these through the day, apply them at the counter or in-app, and they are not official or reference rates. For the rate a regulation names, use the central-bank endpoints.",
  "attribution": {
    "source": "Board rates published by PostFinance on its own website, collected by AllRatesToday",
    "bank_url": "https://www.postfinance.ch/de/support/services/tools-rechner/wahrungsrechner.html",
    "url": "https://allratestoday.com/bank-exchange-rate-api/ch/postfinance/",
    "terms": "Public pages that show the rates need a visible link to allratestoday.com"
  }
}

The board as it stood on a past day:

curl "https://allratestoday.com/api/v1/bank-rates/ch/postfinance?date=2026-11-13" \
  -H "Authorization: Bearer art_live_your_key"

One currency over a date range, one row per day (paid plans; add &format=csv, xml or xlsx for a file):

curl "https://allratestoday.com/api/v1/bank-rates/ch/postfinance/history?ccy=USD&from=2026-11-13&to=2026-11-15" \
  -H "Authorization: Bearer art_live_your_key"

JavaScript

npm install @allratestoday/sdk

import { AllRatesToday } from '@allratestoday/sdk';

const client = new AllRatesToday({ apiKey: 'art_live_your_key' });

// PostFinance's USD row
const r = await client.bankRates('ch', { bank: 'postfinance', ccy: 'USD' });
console.log(`PostFinance buys USD at ${r.buy}, sells at ${r.sell} CHF`);

// The board as it stood on a past day
const past = await client.bankRates('ch', { bank: 'postfinance', date: '2026-11-13' });
console.log(past.snapshot_date, past.rates.length);

Python

import requests

r = requests.get(
    "https://allratestoday.com/api/v1/bank-rates/ch/postfinance",
    headers={"Authorization": "Bearer art_live_your_key"},
    timeout=10,
)
r.raise_for_status()
for row in r.json()["rates"]:
    print(row["ccy"], row["buy"], row["sell"], row["spread_pct"])

Board rate or official rate?

The Swiss National Bank rate is the one tax, accounting and customs rules in Switzerland name; nobody transacts at it. PostFinance's board is the price a customer actually gets. The API puts both on every row: official is the central bank's rate for the same currency and vs_official_pct is how far the bank's mid sits from it. Use the board to show customers a real price, compare banks for a remittance, or keep a dated record of what the bank quoted; use the Swiss National Bank endpoint when a rule asks for the official rate.

FAQ

Where do the PostFinance rates come from?

From the bank's own public rates page (https://www.postfinance.ch/de/support/services/tools-rechner/wahrungsrechner.html), read hourly. AllRatesToday does not change the numbers: each row is the buy and sell price PostFinance shows, with the mid, the spread and the Swiss National Bank rate added.

Are these the official CHF exchange rates?

No. They are PostFinance's retail prices for customers. The official rate in Switzerland is the Swiss National Bank rate, which the API returns as official on each row where the central bank has one, and in full from the central-bank endpoint.

How often is the PostFinance board updated?

AllRatesToday reads the page every hour. The bank's own last-updated stamp is returned as bank_updated_at, so you can tell a fresh read of an unchanged board from a new board.

Can I get PostFinance rates for a past date?

Yes, from 13 November 2026 onward; every day's board is kept permanently. Add ?date=YYYY-MM-DD for one day: the response is the board captured that day, or the nearest earlier day within five days, with date_requested and snapshot_date added. For a range, /history?ccy=USD&from=…&to=… returns one row per day as JSON, CSV, XML or XLSX on paid plans.

Do I need an API key?

Yes. Commercial bank boards need an API key; any plan works, the free key included, and each call counts against the plan. Public pages or widgets that show the rates need a visible link to allratestoday.com.