The Cisco Catalyst C9300-48U is a 48-port UPOE access switch with an 822 W PoE budget on its default 1100 W power supply. Cisco UPOE is rated at 60 W per port, double the PoE+ rating on the 48P, and that is what the tier buys. The PoE budget is only half of the sizing question on this model, because Cisco limits 802.3bt Type 3 to 30 of the 48 ports.
Ports, uplinks and stacking
Access ports on the C9300-48U are 48 ports of 1G copper carrying Cisco UPOE. The tier is the difference from the rest of the line: where a PoE+ port is rated at 30 W, a UPOE port is rated at 60 W, which is what makes the model suitable for endpoints that a PoE+ switch cannot feed at all.
Uplinks are separate from the access count and come from a removable network module, so uplink speed is chosen at order and can be changed later. Stacking is StackWise-480 at 480 Gbps with up to eight members, and every member of a stack has to sit at the same network stack license level.
| Specification | C9300-48U |
|---|---|
| Access ports | 48 x 1G copper, Cisco UPOE |
| PoE budget | 822 W on the default 1100 W supply |
| Per-port rating | Cisco UPOE, 60 W |
| PoE with a 1900 W primary | 1622 W |
| Maximum PoE | 1800 W, limited by design |
| 802.3bt Type 3 | Up to 30 of the 48 ports |
| Uplinks | Modular network module, 1G / mGig / 10G / 25G / 40G |
| Stacking | StackWise-480, 480 Gbps, up to 8 members at the same license level |
| Switching capacity | 256 Gbps, 736 Gbps stacked |
| Forwarding rate | 190.48 Mpps |
| Rack height | 1RU |
| Weight | 17.03 lb |
PoE budget: what this switch can actually power
A Cisco Catalyst C9300-48U carries 48 UPOE ports against an 822 W PoE budget on its default 1100 W power supply. Cisco's footnote is the way to read that: PoE delivery is limited by port number and port rating, so at the UPOE rating of 60 W a port, thirteen ports drawing their full class account for 780 W of the 822 W available. That thirteen-port figure is our arithmetic on Cisco's published inputs and is not itself a Cisco specification.
Headroom on this model is unusually wide and is worth planning against rather than discovering. Moving the primary supply to a 1900 W unit raises the published budget to 1622 W, and Cisco gives 1800 W as the ceiling, footnoted as limited by design. A 48-port UPOE switch is therefore three quite different switches depending on which supply is fitted, and the supply is the line on the order that decides which one arrives.
The 802.3bt Type 3 limit on this model
Cisco attaches a constraint to the 48-port UPOE model that does not apply to the 24-port one, and it is stated in the same breath as the rating: Cisco UPOE at 60 W per port, and IEEE 802.3bt Type 3 on all ports for the 24-port switch, or up to 30 ports for the 48-port switch. On a C9300-48U, 802.3bt Type 3 therefore reaches up to 30 of the 48 access ports.
That is Cisco's own number and it should not be restated as all 48. A deployment where more than 30 endpoints need Type 3 specifically has outgrown this chassis for that requirement, whatever the total budget says, and the honest answer at that point is a second switch rather than a bigger power supply.
Stacking: what this switch can and cannot join
A Cisco Catalyst C9300-48U stacks over StackWise-480 at 480 Gbps with up to eight members in a stack. Cisco's rule on membership is unambiguous: you cannot stack fixed uplink models, which are the C9300L SKUs, with modular uplink models, which are the C9300 SKUs, or with other Catalyst switches such as the 3850 and 3650 Series. Any combination of Catalyst 9300 Series models can form a stack, and separately, any combination of Catalyst 9300L models can form a stack.
A UPOE switch therefore stacks happily with PoE+ and data-only members of the same line, which is the usual shape of a real closet: a few ports that need the higher tier and a majority that do not. Power is not pooled across the stack, so each member keeps its own budget and each has to be sized on the endpoints hanging off it, with the license level matched across all of them.
Uplinks: modular module or fixed ports
Uplinks on the C9300-48U come from a network module, published by Cisco in five forms: C9300-NM-4G for four 1G ports, C9300-NM-4M for four mGig ports, C9300-NM-8X for eight 10G ports, C9300-NM-2Q for two 40G ports and C9300-NM-2Y for two 25G ports. The module is a separate order line and is not fixed for the life of the chassis.
There is no 100G module for the base Catalyst 9300. Those modules are 9300X parts, so a 100G uplink plan means a different platform. Where the access requirement is 1G copper but the uplinks need to be far faster than this line reaches, a Nexus 93180YC-EX answers the same floor plan from the data centre side instead.
Where the C9300-48U sits in the 9300 line
The C9300-48U is the 48-port UPOE member of the modular-uplink Catalyst 9300 family, one tier above the PoE+ models and matched against the 24-port UPOE version of itself.
| Specification | C9300-48U | C9300-24U |
|---|---|---|
| Access ports | 48 UPOE | 24 UPOE |
| PoE budget on the default 1100 W supply | 822 W | 830 W |
| Per-port rating | Cisco UPOE, 60 W | Cisco UPOE, 60 W |
| Maximum PoE | 1800 W | 1440 W |
| 802.3bt Type 3 | Up to 30 ports | All ports |
| Switching capacity | 256 Gbps | 208 Gbps |
| Uplinks | Modular network module | Modular network module |
| Stacking | StackWise-480, 480 Gbps, up to 8 | StackWise-480, 480 Gbps, up to 8 |
On its default 1100 W power supply Cisco publishes an 822 W PoE budget for the C9300-48U and 830 W for the C9300-24U, which is not the direction port count would suggest. That relationship holds at the default supply and reverses above it, because a 1900 W primary takes this switch to 1622 W while the 24-port model caps at 1440 W. Against the PoE+ tier, the C9300-48P is the same 48 ports at half the per-port rating.
Buying refurbished while Cisco still ships new
Cisco still sells the Catalyst 9300 new, so nothing here depends on a lifecycle gap. The refurbished case is price and availability on the same part number, which tends to matter most on the UPOE models, where the higher tier is bought for a specific set of endpoints and the budget for them was set long before the switch was specified.
Whole systems carry a 2 year Enterasource warranty and ship free FedEx Ground to the lower 48 states. Every unit is tested before it leaves. The rest of the Cisco switching range is on the Cisco networking pages.
Condition, testing and what ships with the switch
The process behind every unit is the same, and it is worth setting out in full: inbound test on receipt, disassemble, clean, inventory, pick, assemble, configure, and an outbound test before the switch ships. On a UPOE model the power supply is the line to confirm most carefully, because it is what sets the budget. Supplies beyond the one fitted, network modules, stacking cables and stack kits are all quoted separately.
Software licenses and subscriptions are not included unless the listing states otherwise. Cisco sells the Catalyst 9300 in two network stack levels, Network Essentials and Network Advantage, and they are different part numbers with different feature sets rather than a cosmetic suffix. Tell us which level your network needs before you order and we will confirm, in writing, what the specific unit we are shipping carries.
Frequently Asked Questions
What is the PoE budget of a C9300-48U?
Cisco publishes 822 W on the default 1100 W power supply. Fitting a 1900 W primary raises the published figure to 1622 W, and 1800 W is the ceiling Cisco gives for the model, footnoted as limited by design. All three are totals shared across the 48 access ports rather than per-port guarantees, so the figure that decides a build is the sum of what the connected endpoints draw in their real class.
What is the difference between a C9300-48P and a C9300-48U?
The power tier, and the budget that follows from it. Both carry 48 ports of 1G copper with the same 256 Gbps of switching capacity, the same modular uplink module and the same StackWise-480 stacking. The 48P runs PoE+ at 30 W per port with 437 W of budget on its 715 W supply; the 48U runs Cisco UPOE at 60 W per port with 822 W on its 1100 W supply.
What uplinks does a C9300-48U take?
A removable network module, and Cisco publishes five: C9300-NM-4G for four 1G ports, C9300-NM-4M for four mGig ports, C9300-NM-8X for eight 10G ports, C9300-NM-2Q for two 40G ports and C9300-NM-2Y for two 25G ports. There is no 100G module for the base Catalyst 9300, so a requirement for 100G uplinks points at a different platform rather than a different module.
Can a C9300-48U be stacked with a C9300L?
No. Cisco states that fixed uplink models, the C9300L SKUs, cannot be stacked with modular uplink models, the C9300 SKUs, or with other Catalyst switches such as the 3850 and 3650 Series. Inside the line it is permissive: any combination of Catalyst 9300 models can form a stack, so a UPOE switch stacks with PoE+ and data-only members, as long as every member shares the same network stack license level.
How many UPOE ports does a C9300-48U have?
All 48 access ports carry Cisco UPOE at the 60 W per-port rating. The more useful half of the answer is the one buyers miss: Cisco specifies IEEE 802.3bt Type 3 on up to 30 ports for the 48-port switch, against all ports on the 24-port version. So 48 ports are UPOE, and up to 30 of them are Type 3, and those are two different numbers.
Does a refurbished C9300-48U include a Cisco license?
Licenses and subscriptions are not included unless the listing says so. The UPOE tier and the network stack level are unrelated: the tier is a hardware property that sets what the ports can deliver, while the level is a software entitlement recorded in the part number, and a unit can carry the higher power tier at either level. Tell us which level the network needs and we will confirm in writing what the unit carries.
