Qualifying loss and matched-bet ratings, explained

Two fields decide whether a matched bet is worth placing: the rating and the qualifying_loss. The rating measures how close a bookmaker's back price is to the current exchange lay price for the same selection: the higher the rating, the less you give up by matching the bet. The qualifying loss is the small, expected loss on the qualifying bet you place to release a free bet or offer. This post explains both honestly, without inventing a formula, and shows how a matched feed computes them so you do not have to.

What does the rating field mean?

The rating measures how close a back price is to the lay price for the same selection at the same moment. Near the top of the scale, the back and lay odds are almost level, so matching the bet costs you very little. Lower down, the gap is wider, and you give up more to cover the position. It is a single number that lets a scanner sort hundreds of selections by how tight the match is, without you reading every pair of prices by eye.

Think of it as a quality score for a back/lay pair, not a profit figure. A bet365 price of 2.10 sitting against a Betfair lay of 2.14 is a tight match and rates high. The same back price against a lay of 2.40 is a loose match and rates lower, because closing the position costs more. We do not publish the exact scoring weights, but the direction never changes: tighter pair, higher rating.

What is qualifying loss?

Qualifying loss is the small, expected loss on a qualifying bet: the bet you place to meet the terms of an offer before a free bet or bonus is released. You back a selection at the bookmaker and lay the same selection at an exchange. Because the back and lay odds are rarely identical, and the exchange charges commission on a winning lay, the two sides do not cancel out perfectly. The difference is the qualifying loss, usually a small negative figure carried in the data as qualifying_loss.

Conceptually it comes from three inputs: the back stake at the bookmaker, the lay stake at the exchange, and the exchange commission. The closer the back and lay prices, the smaller the gap, which is why a high rating and a near-zero qualifying_loss tend to move together. We describe it as a cost, not a guaranteed outcome: it is the expected loss on the qualifier itself, before any free bet or offer value is considered.

How do rating and qualifying loss sit in the data?

Both fields ride on the same row as the matched prices that produced them. Each row carries the event, market and selection, the bookmaker back price, the paired exchange lay price with its liquidity, and then the two derived fields. Here is the shape of a single row (illustrative, not live data):

{
  "event": "Brighton vs Newcastle",
  "market": "match_odds",
  "selection": "Brighton",
  "back": { "bookmaker": "bet365", "odds": 2.50 },
  "lay":  { "exchange": "betfair", "odds": 2.54, "liquidity": 1320 },
  "rating": 98.7,
  "qualifying_loss": -0.21
  // ... region, feed_type and freshness fields elided
}

Read the row from the prices outward. The back of 2.50 and the lay of 2.54 are close, so the rating of 98.7 is high and the qualifying_loss of -0.21 is small. The liquidity figure tells you the lay is real and not a price you could never get filled at. For the full envelope and every field on the row, see the anatomy of a response.

Why compute them in the feed instead of in your app?

Because computing them yourself means owning two problems at once: collecting the prices, and matching them. To produce a rating and a qualifying_loss you need the bookmaker back price and the current exchange lay price for the same selection, aligned to the same moment, with enough liquidity for the lay to count. A matched feed does that pairing before you receive the data, across 60+ UK books with bet365 included, against three exchanges: Betfair, Smarkets and Matchbook.

That is the difference between a price and an opportunity. A raw odds source hands you back numbers and leaves the matching, the rating and the qualifying-loss maths to you. A matched feed hands you the finished row, so your oddsmatcher or scanner renders sorted, ready-to-place results from the first call. The wider context for that trade-off is in the matched-betting data guide.

How to read the two together

Use the rating to shortlist and the qualifying loss to confirm. The rating sorts the field so the tightest matches surface first; the qualifying loss tells you the expected cost of the specific qualifier you are about to place. A high rating with a small qualifying loss is a clean qualifier. A lower rating with a wider qualifying loss is one to weigh against the offer it releases.

• `rating`: how close back and lay sit. Higher means less given up matching the bet. Use it to rank.
• `qualifying_loss`: the expected cost of the qualifying bet itself, a small negative figure. Use it to decide.
• `liquidity`: how much you can actually lay at the quoted price. A great rating on a thin lay is not really placeable.

Neither field is a profit guarantee, and we never present them as one. They are tools for sorting and sizing a position. The offer or free bet sitting behind a qualifier is what turns an expected small loss into a worthwhile bet, and that judgement stays with you. For how these fields feed an oddsmatcher view, see oddsmatcher data, explained.

The short answer

The rating tells you how close a back price is to the exchange lay price, so a higher rating means a tighter, cheaper match. The qualifying loss is the small, expected cost of the qualifying bet that releases an offer. A matched feed computes both on every row, against three exchanges, so you skip building a matcher and start with finished data. You can see the fields on real rows in the API docs, or get the full UK feed, bet365 included, with a free trial. It powers a leading UK matched-betting platform today.