TUNINDEX & TUNINDEX20: Calculation & 2026 Roster

Mizen editorial team · published 30/10/2026 · checked 30/10/2026 · Translation; the French version is authoritative

TUNINDEX and TUNINDEX20 are the two benchmark indices of the Tunis Stock Exchange. Here is how they are calculated, what “free float” covers and how the twenty securities are selected.

TUNINDEX: role, history and nature

TUNINDEX is the benchmark index of the Tunisian stock market, based at 1000 on 31 December 1997. It measures the main equity market. It is also calculated in US dollars (USD) and euros (EUR).

It is a total return index: dividends are reinvested. It cannot therefore be compared to the CAC 40, a price index; the Parisian equivalent would be CAC 40 GR.

It includes all main market securities listed for more than one month, with a single line per issuer (the most active). A security is removed if it moves to Compartment S (compartiment S) or remains suspended for more than 2 months.

Quarterly reviews (December, March, June, September), effective on the first business day of January, April, July and October.

Calculation and free float

TUNINDEX is weighted by free-float market capitalisation. Its official formula:

I(t) = 1000 × Σ(Qᵢ × Fᵢ × fᵢ × Cᵢ) / (k(t) × CB⁰)

Q is the number of securities, F the free-float factor, f the capping factor, C the price, CB⁰ the base market capitalisation and k the adjustment coefficient ensuring continuity during corporate actions.

The price Cᵢ used is the closing price: the last traded price (see prices) or the static reservation threshold. A reserved security therefore enters the index at the threshold, even without transactions. See the guide to reservation thresholds.

The free float excludes treasury shares, the State and public enterprises, founders, shareholders acting in concert and insiders, controlling blocks and stable holdings (over 5%).

It is rounded up to the nearest 10% band, unless it falls within [10% ; 11%[, [20% ; 21%[, etc., and reviewed every year based on end-of-November data, taking effect in January.

Example. A company whose calculated free float is 24% (after excluding the State, founders and stable holdings) is assigned a free-float factor of 30% (Fᵢ = 0.30), the next higher 10% band.

Finally, no single security can account for more than 15% of the index (capping factor).

TUNINDEX20: selection and variants

TUNINDEX20 has a base of 1000 points on 31 December 2006. It includes the 20 largest and most liquid securities in the market traded continuously. Like TUNINDEX, it is a total return index, with dividends reinvested.

The Tunis Stock Exchange also calculates two variations:

TUNINDEXprice20, calculated on prices alone, without dividends;
TNVWAP20, calculated from the volume-weighted average price, with free float rounded in 5% steps and capped at 10%.

Selection starts from the top 25 free-float market capitalisations in continuous trading. The 15 largest meeting a minimum turnover rate (the 10^th percentile) are selected first. The remaining 5 are chosen from the remaining 10 according to a grid combining size and liquidity: traded capital, turnover rate, trading frequency, and tightness of the bid-ask spread.

The ordinary review takes place once a year, in December. Extraordinary reviews may occur in March, June and September: fast exit of a security falling beyond the 25^th rank, switching to auction, transferred to Compartment S (compartiment S) or remaining suspended for more than two months; fast entry of a non-constituent reaching the 15^th rank or better.

Composition and governance

The indices fall under the Stock Index Committee (Comité des indices boursiers), which brings together at least twice a year the Ministry of Finance, the CMF, the BCT, the INS, the ITCEQ and two academics.

At its meeting of 25 September 2026 (notice no. 59), the Committee modified the composition of TUNINDEX20 effective 1^st October 2026: ATL was included with a free-float factor of 30%, while Tunisie Leasing & Factoring was removed.

Since 1^st October 2026, the twenty constituent securities of TUNINDEX20 are: AMEN BANK, ATB, ATL, ATTIJARI BANK, BIAT, BNA, BT, CARTHAGE CEMENT, CITY CARS, DÉLICE HOLDING, ONE TECH HOLDING, POULINA GP HOLDING, SAH, SFBT, SOTUVER, STAR, STB, TPR, UIB and UNIMED.

The next annual review takes place in December 2026, taking effect in January 2027. The rules described here are those of the Tunis Stock Exchange index guide, updated in 2023.

Frequently asked questions

What is the TUNINDEX?

The benchmark index of the Tunis Stock Exchange: base 1000 on 31/12/1997, weighted by free-float market capitalisation, dividends reinvested. It covers main market securities listed for more than one month.

How is the TUNINDEX calculated?

By the sum of free-float market capitalisations (shares × free float × capping × closing price), divided by the base capitalisation adjusted by an adjustment coefficient. A reserved security enters at its threshold.

What is the difference between TUNINDEX and TUNINDEX20?

TUNINDEX covers the entire main market; TUNINDEX20 includes the 20 largest liquid securities in continuous trading (base 1000 on 31/12/2006). The latter also has a price version (TUNINDEXprice20) and a volume-weighted average price version (TNVWAP20).

What is the composition of TUNINDEX20 in 2026?

Since 1^st October 2026 (notice no. 59 of the Comité des indices), ATL replaced Tunisie Leasing & Factoring; the complete list appears above. Next review: December 2026.

What does the year-to-date performance of TUNINDEX measure?

The variation of the main market, dividends reinvested, since the last close of the previous year: it is not directly comparable as is to that of a price index. The Mizen Indices page displays today's levels.

Sources

General information; not tax advice and not an investment recommendation.