Munich Re and Swiss Re Post Sub-80% Ratios Atop AM Best's 50 Largest Reinsurers

Munich Re heads AM Best's 2026 ranking of the world's 50 largest reinsurers with a 73.5% combined ratio, ahead of Swiss Re at 79.5%, and the five largest IFRS 17 reporters posted a weighted 80.0% combined ratio, improved from 84.9% (AM Best, via Insurance Journal, August 2026). A ranking that documents record margins is, in the same breath, documenting the reason cedents expect to pay less.

Key Takeaways

• AM Best now publishes the list as two books rather than one, splitting IFRS 17 reporters from the rest, because revenue under the standard is not comparable to gross written premium.
• Comparing across the split is not like for like. IFRS 17 discounting flatters the ratio by roughly 11 points across the big four on long-tail books.
• The ordering is a currency artifact. The euro gained 12.9% against the dollar in 2025; Munich Re's reinsurance revenue fell 3.7% before that effect and Swiss Re's fell 4.5%. Both leaders contracted.
• The 46.2% concentration figure is a share of one cohort, not of the whole ranking. Read as two firms writing half the world's reinsurance, the arithmetic does not survive.

Two Rankings, Not One

AM Best split the list because revenue under IFRS 17 is not comparable to gross written premium. Munich Re leads the IFRS 17 side at $35.4 billion of reinsurance revenue, followed by Swiss Re at $34.5 billion and Hannover Re at $31.5 billion. Lloyd's leads the non-IFRS 17 side at $27.1 billion of gross written premium, ahead of Berkshire Hathaway at $25.4 billion and Reinsurance Group of America at $17.5 billion.

The split matters for anyone using the table as a benchmark. Comparing Munich Re's 73.5% to Lloyd's 85.6% is comparing a discounted ratio against an undiscounted one. Under IFRS 17 the liability for incurred claims is discounted and the unwind flows through insurance finance expense rather than the combined ratio, which mechanically flatters the ratio by several points on long-tail books. The site's coverage of the H1 2026 prints put that effect at roughly 11 points across the big four.

A cedent benchmarking its reinsurer panel across the two halves of this ranking is not comparing like with like, and the gap is widest precisely where it matters most, on the casualty treaties where discounting does the most work.

What the Rankings Do and Do Not Say

Group	Basis	2025 reinsurance revenue / GWP	Combined ratio	Volume signal
Munich Re	IFRS 17	$35.4B	73.5%	Down 3.7% pre-forex
Swiss Re	IFRS 17	$34.5B	79.5%	Down 4.5%
Hannover Re	IFRS 17	$31.5B	84.0%	Non-life up 0.6%, life up 3.9%
SCOR	IFRS 17	n/d	n/d	Non-life down 4.5%, life down 4.8%
China Re	IFRS 17	n/d	n/d	Non-life down 5.6%, life up 3.5%
Lloyd's	Non-IFRS 17	$27.1B	85.6%	Up 7.1% pre-forex
Berkshire Hathaway	Non-IFRS 17	$25.4B	84.5%	Down 7.9%
RGA	Non-IFRS 17	$17.5B	n/d	Life premium up 12.3%
RenaissanceRe	Non-IFRS 17	n/d	n/d	Growth below 0.1%

Munich Re took first place from Swiss Re without writing more business. The euro appreciated 12.9% against the US dollar during 2025 and sterling gained 7.4%, which is enough on its own to reshuffle a table denominated in dollars. Munich Re's reinsurance revenue fell 3.7% before the currency effect; Swiss Re's fell 4.5%. Both leaders contracted, and the two "continue to trade places" as exchange rates move, because Munich Re reports in euros and Swiss Re in dollars.

That is worth stating plainly because rank-order changes get reported as competitive news. Nothing in the swap tells a reserving or pricing actuary anything about relative underwriting performance. The pre-currency revenue lines do, and they point the same direction for both: a shrinking top line at the two largest reinsurers in the world, the volume signal the site tracked through Munich Re's guidance cut to €38 billion.

The concentration figure needs the same treatment. The headline that travelled furthest is that Munich Re and Swiss Re together account for 46.2% of the reinsurance revenue recorded in the ranking. Read as two firms writing nearly half the world's reinsurance, that would be a serious competition finding. The arithmetic says otherwise.

Munich Re's $35.4 billion plus Swiss Re's $34.5 billion is $69.9 billion. If that pair were 46.2% of the whole top 50, the entire list would total roughly $151 billion. AM Best's 2022 edition put top-50 gross premiums written at $363.6 billion, and nothing in this market shrank by 58% in three years. The 46.2% is a share of the IFRS 17 cohort, not of all fifty groups, and the honest statement is that two firms dominate one half of a ranking AM Best deliberately stopped presenting as a single market.

The practical consequence runs opposite to the headline. A cedent's negotiating position is set by how many rated, appetite-carrying markets will quote its programme, and that pool includes Lloyd's syndicates, Berkshire, Everest, RenaissanceRe and the Bermuda and ILS capacity behind them. Global reinsurance capital reached a record $790 billion at 31 March 2026, with alternative capital at $141 billion. That supply, not the concentration ratio, sets the price.

A Ranking That Documents Its Own Undoing

The margins in this table are the argument against them. Guy Carpenter's Global Property Catastrophe Rate-on-Line Index has fallen 16% across the 2026 renewal rounds and sits 23% below its 2024 peak. A cedent walking into a January renewal with a published 73.5% combined ratio on the other side of the table has a straightforward case, and it does not require any claim about the reinsurer's cost of capital.

The awkwardness for the reinsurers is that neither of the two corrections above helps them make the counter-argument. The IFRS 17 discount that flatters the headline ratio is not something a reinsurer wants to explain at a renewal, because the explanation concedes that several points of the margin are an accounting artifact rather than underwriting. The currency effect that lifted Munich Re to first place cuts the same way, since the pre-currency revenue decline is the evidence that volume is already being surrendered.

That leaves the concentration figure as the only one of the three that a reinsurer could use, and it is the one that does not survive checking. A market where two firms genuinely wrote half the capacity would be a market with pricing power. A market with $790 billion of capital, $141 billion of it alternative, and a rate index down 23% from peak is the opposite, and the ranking's own two-book structure is the clearest admission of it.

The ranking is therefore most useful read backwards. It is not a league table of who is winning; it is a record of the conditions under which the next two renewal rounds get negotiated, published by the agency whose ratings the same cedents will cite when they ask for a lower price.

Further Reading on actuary.info

• Fitch: Big Four Reinsurers' Record 21.5% ROE Masks Price Cuts Still to Earn Through - the half-year view of the same companies, including the 11-point IFRS 17 discount effect.
• Munich Re Cuts Reinsurance Revenue Guidance to €38B After July Renewals - the volume-versus-price trade behind Munich Re's shrinking top line.
• Swiss Re's 76.7% Combined Ratio Hides a Widening Loss-Pick Gap - what raising loss assumptions into a falling price looks like in practice.
• Munich Re Cuts While Hannover Re Grows: The Mid-Year 2026 Volume Divergence - competing readings of where the pricing floor sits.
• AM Best: Record Capital Tests Reinsurance's 87% Combined Ratio - the reserve-cushion question across the broader peer set.
• July 1 Property Cat Rate-on-Line and the Reinsurer Cost-of-Capital Math - the mid-year renewal that produced the 16% index decline.
• AM Best on Third-Party Capital Growth Deceleration - the alternative-capital half of the supply picture.
• Cheaper Reinsurance Puts P&C Pricing Actuaries in a Bind - how the same softening reaches primary rate filings.